1. Letters patent for a process, irrespective of the particular
mode or form of apparatus for carrying it into effect, are
admissible under the patent laws of the United States.
2. To sustain such letters, the patentee should be the first and
original inventor of the process and claim it in them. If the means
of carrying it out are not obvious to ordinary mechanics skilled in
the art, his specification should describe some mode of carrying it
out which will produce a useful result.
3. A party who subsequently discovers a new mode of carrying out
a patented process and obtains letters patent therefor is not
entitled to use the process without the consent of the patentee
thereof.
4.
Mitchell v.
Tilghman, 19 Wall. 287, reviewed and overruled, and
the letters patent No. 11,768, granted Oct. 3, 1854, to Richard A.
Tilghman and subsequently renewed and extended, relating to the
manufacture of fat acids, sustained as letters for a process.
5.
O'Reilly v.
Morse, 15 How. 62, and
Neilson v.
Thompson, Web.P.C. 276, commented upon and explained.
This is a suit in equity brought by Richard A. Tilghman against
William Proctor, James Gamble, W. A. Proctor, James N.
Page 102 U. S. 708
Gamble, and George H. Proctor, complaining of their infringement
of letters patent No. 11,766, granted to him, bearing date Oct. 3,
1854, and subsequently renewed and extended, for a process for
obtaining free fat acids and glycerine from fatty bodies. The
answer denies the validity of the letters and the alleged
infringement of them. On a final hearing upon the pleadings and
proofs, the bill was dismissed, and he appealed. The case is fully
stated in the opinion of the Court.
MR. JUSTICE BRADLEY delivered the opinion of the Court.
This case involves a consideration of the same patent which was
the subject of litigation in the case of
Mitchell
v. Tilghman, reported in 19th Wallace 287. The
evidence in the present case, which is quite an unwieldy mass, is
much the same as in that, being supplemented, however, by the
testimony of the patentee respecting the nature of his original
experiments and the practicability of using profitably the coil
apparatus described in the patent, together with certain exhibits
relating to the novelty of the alleged invention. Upon the renewed
consideration which has been given to the subject, the Court is
unanimously of opinion, contrary to the decision in the
Mitchell case, that the patent of Tilghman must be
sustained as a patent for a process, and not merely for the
particular mode of applying and using the process pointed out in
the specification, and that the defendants have infringed it by the
processes used by them.
The patent in question relates to the treatment of fats and
oils, and is for a process of separating their component parts so
as to render them better adapted to the uses of the arts. It was
discovered by Chevreul, an eminent French chemist, as early as
1813, that ordinary fat, tallow, and oil are regular chemical
compounds, consisting of a base which has been termed glycerine,
and of different acids, termed generally fat acids, but
specifically, stearic, margaric, and oleic acids. These acids, in
combination severally with glycerine, form stearine, margarine, and
oleine. They are found in different
Page 102 U. S. 709
proportions in the various neutral fats and oils, stearine
predominating in some, margarine in others, and oleine in others.
When separated from their base (glycerine), they take up an
equivalent of water, and are called free fat acids. In this state
they are in a condition for being utilized in the arts. The stearic
and margaric acids form a whitish, semi-transparent, hard
substance, resembling spermaceti, which is manufactured into
candles. They are separated from the oleic acid, which is a thin
oily fluid, by hydrostatic or other powerful pressure, the oleine
being used for manufacturing soap and other purposes. The base,
glycerine, when purified, has come to be quite a desirable article
for many uses.
The complainant's patent is dated the third day of October,
1854, and relates back to the ninth day of January of that year,
being the date of an English patent granted to the patentee for the
same invention. It has but single claim, the words of which are as
follows:
"Having now described the nature of my said invention and the
manner of performing the same, I hereby declare that I claim as of
my invention the manufacturing of fat acids and glycerine from
fatty bodies by the action of water at a high temperature and
pressure."
In the case of Mitchell, the majority of the Court was of
opinion that in the application of the process thus claimed, the
patentee was confined to the method of using the process
particularly pointed out in the specification, and as by that it
was proposed to produce a very rapid separation of the fatty
elements by the use of a high degree of heat, the operation being
effected in the space of ten minutes by forcing the fat, mixed with
water, through a long coil of strong iron tube passing through an
oven or furnace where it was subjected to a temperature equal to
that of melting lead, or 612� Fah., it was concluded by the Court
that the producing of the same result in a boiler subjected to only
400� Fah. and requiring a period of several hours to effect the
desired separation was not an infringement of the patent, although
the process by which the effect was produced -- namely, the action
of water in intimate mixture with the fat at a high temperature and
under a sufficient pressure to prevent the formation of steam --
was undoubtedly
Page 102 U. S. 710
the same. On further reflection, we are of opinion that in the
case referred to, sufficient consideration was not given to the
fact that the patent is for a process, and not for any specific
mechanism for carrying such process into effect.
In order to have a clearer understanding of the question, it is
necessary to advert briefly to the history of the art and then to
examine the terms of the patent in greater detail.
It is conceded by the complainant that two different processes
for effecting a decomposition of fats into their component elements
had been in practical operation prior to his invention. These
processes were called respectively the alkaline saponification
process and the sulphuric acid distillation process. The first
consisted of the manufacture of the fat into soap by the use of
lime or other alkali, and then of the decomposition of the soap so
produced into the fat acids by the aid of hydrochloric or dilute
sulphuric acid. The decomposition of the soap was, by a subsequent
improvement, effected by distillation in an atmosphere of steam.
The other process, called the sulphuric acid distillation process,
consisted of the direct saponification of fat by means of
concentrated sulphuric acid and the subsequent distillation over of
the resulting fatty acids. By this process, however, the glycerine
was destroyed.
The first of these processes was patented by Gay Lussac and
Chevreul in 1825, but was not brought into successful operation in
the manufacture of stearic candles until improved by De Milly in
1831. The second process was proposed and developed between 1840
and 1850. It was extensively used during and after that period by
the large manufacturing firm of E. Price & Co., of London, and
their successors, Price's Patent Candle Company. Mr. G. F. Wilson,
one of the shareholders in that establishment, and apparently a man
of accurate knowledge on this subject, read various papers
illustrative of the history of the manufacture before learned
societies in England, extracts from which are contained in the
record, and throw considerable light on the matter. It appears from
his statements that the distillation of the saponified fat, whether
saponified by an alkali or by sulphuric acid, was often accompanied
by prejudicial effects from the access of atmospheric air to the
contents of the still. To remedy this,
Page 102 U. S. 711
he and his associates adopted and patented the introduction of
superheated steam into the still or vat containing the fat acids,
which excluded atmospheric air, and carried over the fatty vapors
into the receiver in a more perfect condition than they had before
been able to obtain them. These patents were taken out in 1843. In
the following year, the same parties, Gwynne and Wilson, found what
Dubrunfaut had found two or three years before -- that palm oil,
which is very fusible and manageable, can be distilled in its crude
state in the manner last described -- that is, by the introduction
of steam into the still -- without the intervention of
saponification, and the distilled product being then steam boiled
in water, acidulated with sulphuric acid, and the water allowed to
settle and separate, the resulting substance would be a fat acid.
It is not shown that this process was ever carried into successful
operation prior to Tilghman's patent, and judging from what was
done by the Price Patent Candle Company in the way of improvement
immediately after becoming acquainted with Tilghman's process, it
is to be inferred that the steam distillation process (without
saponification) was still an unsuccessful experiment when his
patent was issued. This experiment, however, must be regarded as
the nearest approach to the process of Tilghman of anything done in
the art prior to it.
We do not regard the accidental formation of fat acid in
Perkins's steam cylinder from the tallow introduced to lubricate
the piston (if the scum which rose on the water issuing from the
ejection pipe was fat acid) as of any consequence in this inquiry.
What the process was by which it was generated or formed was never
fully understood. Those engaged in the art of making candles, or in
any other art in which fat acids are desirable, certainly never
derived the least hint from this accidental phenomenon in regard to
any practicable process for manufacturing such acids.
The accidental effects produced in Daniell's water barometer and
in Walter's process for purifying fats and oils preparatory to soap
making are of the same character. They revealed no process for the
manufacture of fat acids. If the acids were accidentally and
unwittingly produced, whilst the operators were in pursuit of other
and different results, without exciting
Page 102 U. S. 712
attention and without its even being known what was done or how
it had been done, it would be absurd to say that this was an
anticipation of Tilghman's discovery.
Nor do we regard the patent of Manicler, which was taken out in
1826, as anticipating the process of Tilghman. It is true that he
directs a mixture of fat with about one quarter of its weight of
water to be placed in a boiler, and subjected to a heat sufficient
to create a pressure equal to one atmosphere above the natural
atmospheric pressure (or about 250� Fah.), the boiler being
provided with a safety valve which would secure that degree of
pressure. But, subject to this pressure, the patent directed that
the mixture should be made to boil, and of course that the water
should be converted into steam: the words are, "Apply fire to this
digester to melt and digest the contained tallow or fat and water
and keep up a rapid ebullition during about six hours." It is
probable, therefore, that any decomposition of the fat which may
have been produced by this process was due to the steam formed and
passing through the fat, as no means appears to have been adopted
for keeping up the mixture of the fat and water. But we have no
evidence that the process was ever successful in practice. One of
the defendants' witnesses testifies that he tried it, and though he
got some results, he adds this pregnant observation: "To transform
all the fat in this way at so low a temperature would have required
many days." He only pretends that the sample which he obtained
showed by its appearance, as well as by its acid action, that the
separation had commenced. Evidently, therefore, this was but an
abandoned experiment, since we never hear any more of it from 1826
down to the trial of this cause.
It is unnecessary to examine in detail other alleged
anticipations of Tilghman's process. We believe that we have
specified the most prominent and reliable instances.
Tilghman's discovery was made in 1853, and was, in brief,
this:
"That the fat acids can be separated from glycerine without
injury to the latter by the single and simple process of subjecting
the neutral fat, whilst in intimate mixture with water, to a high
degree of heat under sufficient pressure to prevent the water from
being converted into steam, without the
Page 102 U. S. 713
employment of any alkali or sulphuric acid or other saponifying
agent, the operation, even with the most solid fats, being capable
of completion in a very few minutes when the heat applied is equal
to that of melting lead, or 612� Fah., but requiring several hours
when it is as low as 350� of 400� Fah. The only conditions are a
constant and intimate commixture of the fat with the water, a high
degree of heat, and a pressure sufficiently powerful to resist the
conversion of the water into steam. The result is a decomposition
of the fatty body into its elements of glycerine and fat acids,
each element taking up the requisite equivalent of water essential
to its separate existence, and the glycerine in solution separating
itself from the fat acids by settling to the bottom when the mixed
products are allowed to stand and cool. In this process, a chemical
change takes place in the fat in consequence of the presence of the
water and the active influence of the heat and pressure upon the
mixture."
We are satisfied that Tilghman was the original discoverer of
this process. His priority was acknowledged at the time by those
most interested to question it. Mr. Wilson, to whose statements
reference has been made and who is perhaps more justly entitled
than anyone else to claim an anticipation of Tilghman's discovery,
makes no such pretension, but, on the contrary, concedes Tilghman's
right to priority, and indeed Price's Patent Candle Company, of
which Mr. Wilson was a member and director, took a license under
Tilghman's English patent.
As having some bearing upon the proper construction of the
patent in suit (which will presently be more particularly
examined), it is proper to observe that Tilghman's actual
invention, as demonstrated in his experiments made in 1853, before
making any application for a patent, was not confined to the use of
a coil of pipe in a heated chamber or furnace for effecting the
process which he claims, but was frequently exhibited by using a
simple digester, filled nearly full with a mixture of fat and
water, and heated in a gas stove or in a vertical position over a
gas lamp, the mixture of fat with the water being kept up by a
loose metallic rod or jumper, which thoroughly mixed the contents
when the digester was shaken. Sometimes
Page 102 U. S. 714
the digester was heated in a horizontal position, and, being
provided with thin copper partitions fixed inside, was made to
revolve in order to cause a more perfect mixture of the materials.
In using the digester, it not being provided with a safety valve, a
small space was left at the top for the formation of sufficient
steam to prevent, by its elasticity, the vessel from exploding.
In making these experiments, Tilghman not only varied the
apparatus, but applied different degrees of heat in the operation.
The following is his account of some of these proceedings. He
says:
"Before applying for my patent, I had made many experiments in
decomposing by water at temperatures below melting bismuth,
sometimes in the coil form of apparatus, but most frequently in
digesters. The lowest temperature tried by me was three hundred and
fifty degrees Fah. (350� F.), or 120 pounds pressure continued for
four hours. The digester was as usual in a vertical position, but
the heat was in this case given by an oil bath. I obtained both fat
acids and glycerine in this experiment, but in such small
quantities as to prove that though the decomposition did go on at
that heat, yet it was very slow compared with the higher heats. I
find notes of another experiment, July 15, 1854, in the coil
apparatus, with palm oil, made at the melting point of tin, 440�
Fah., 360 pounds pressure. It was pumped through the coil very
slowly, so as to give about thirty minutes' heat, and found to be
partly decomposed, so that it was returned to the inlet end of the
apparatus and pumped through a second time at the same rate and
heat, which produced perfect decomposition of the palm oil into fat
acids and solution of glycerine. Ten minutes' exposure would have
perfectly decomposed palm oil at the heat of melting bismuth, 510�
Fah. Yet I found 70� lower heat required six times as long to
produce the same effect. I had often decomposed tallow at 510� Fah.
before taking out my patent, not in the coil apparatus, but in the
simple vertical digester. In this case, I had to allow increased
time on account of the imperfect contact of the fat and water in
addition to that required by the diminished temperature."
In the course of his testimony, Tilghman explains why, in his
patent, he specially recommended the use of the high
temperature
Page 102 U. S. 715
of melting lead in applying his process to practical use. He
says:
"Many experiments had shown me that at these higher temperatures
the decomposition was carried on with the greatest economy of fuel
and cost of apparatus. When in London in 1847, I had found Perkins'
house warming apparatus, consisting of coils of hundreds of feet of
pipe, containing water at the temperature of melting lead, had long
been in extensive domestic use there. On returning to London in
1853, I found the same apparatus largely used for heating bakers'
ovens. As I thus found such heats and pressures were perfectly
practical and safe, as well as economical, I thought I was bound to
describe my invention in what I then believed to be the best mode
of carrying it out, and that, as I was the discoverer of the
chemical fats, I could then claim broadly as my process the use of
water highly heated and under pressure to decompose fats, no matter
what temperature or apparatus was used."
And being asked for his present view as to the practicability,
economy, and safety of the higher temperatures as compared with
lower temperatures, he said:
"I think the high pressure apparatus is much more economical,
both in the first cost and in the expense of working. Its principal
disadvantage is that ordinary engineers are not familiar with its
management, and consequently dislike it."
In December, 1853, Tilghman, having completed his experiments to
his own satisfaction, filed a caveat in the Patent Office
preparatory to taking out a patent for his invention. In this
caveat he says:
"The invention consists in subjecting animal and vegetable fatty
and oily substances containing glycerine to a high temperature and
pressure in close vessels, mixed with different agents, according
to the effect desired to be produced upon the fatty matter. Thus,
when I wish to convert the neutral fatty substances into fatty
acids and glycerine, I pump a mixture of the fat and water, under
great pressure, through a series of strong metal tubes, kept at
about the heat of melting lead, and provided with a cooling worm
and safety valve at its outlet. The neutral fatty substance is
decomposed by the process, and the fat acid and solution of
glycerine which issue through the safety valve separate by
settling. "
Page 102 U. S. 716
Tilghman soon after repaired to England and took out a patent
there, dated the ninth day of January, 1854, and sealed the 25th of
March. He immediately put in operation an apparatus for exhibiting
his process on a small scale. Mr. Wilson, before mentioned,
witnessed his experiments, and thus speaks of them in a paper
communicated to the Journal of the Society of Arts, Jan. 25,
1856:
"In January, 1854, Mr. Tilghman, an American chemist who has
studied all that has been published here and in France on the
subject of acidification and distillation of fatty bodies, obtained
a patent for exposing fats and oils to the action of water at a
high temperature and under great pressure in order to cause the
combination of the water with the elements of the neutral fats, so
as to produce at the same time free fat acids and solution of
glycerine. He proposed to effect this by pumping a mixture of fat
and water by means of a force pump through a coil of pipe heated to
about 612� Fah., kept under a pressure of about 2,000 pounds to the
square inch, and he states that the vessel must be closed, so that
the requisite amount of pressure may be applied to prevent the
conversion of water into steam. This is, all must admit, a
beautiful, original, chemical idea, well carried out; it has yet to
prove how far it can compete successfully with distillation. We
have made an arrangement with Mr. Tilghman which will give us the
means of testing its commercial merits."
Mr. Wilson goes on to state that this process of Tilghman
suggested to them the idea of distilling fats by passing steam into
them at a high temperature whereby to resolve them into glycerine
and fat acids. They found the plan successful, and that the
glycerine distilled over with the fat acids, but no longer combined
with them, and, in July, 1854, they took out a patent for that
process. In a paper read before the Glasgow meeting of the British
Association for the Advancement of Science in September, 1855, Mr.
Wilson thus refers to the course of discovery which took place in
this branch of manufacture:
"By our first improvement in separating the fat acids from
neutral fats, the glycerine was decomposed by the direct action of
concentrated sulphuric acid at a high temperature, and all that
remained of it was a charred precipitate. A new process for
decomposing
Page 102 U. S. 717
neutral fats by water under great pressure coming under our
notice [referring to Tilghman's process] led us to look again more
closely into our old distilling processes, and the doing this
showed, what we had often been on the brink of discovering, that
glycerine might be distilled."
"In our new process, the only chemical agents employed for
decomposing the neutral fat and separating its glycerine are steam
and heat, and the only agents used in purifying the glycerine thus
obtained are heat and steam; thus all trouble from earthy salts or
lead is escaped."
"Distillation, however, purifies the impure glycerine of the old
sources."
"On the table is a series of products of palm oil, which will
serve to illustrate the process. Steam, at a temperature of from
550� to 600� Fah., is introduced into a distillery apparatus
containing a quantity of palm oil. The fatty acids take up their
equivalents of water, and the glycerine takes up its equivalent;
they then distil over together. In the receiver the condensed
glycerine, from its higher specific gravity, sinks below the fat
acids."
We quote more fully from this paper because it is a contemporary
acknowledgment, made by a man who stood in the front rank of those
who, understood, and whose interest it was to understand, the most
advanced process of resolving fats and oils into their component
parts, that Tilghman's "process for decomposing neutral fats by
water under great pressure" was "a new process," and who, with his
associates, took hints from it for making new departures and
improvements in the art. The statements of Mr. Wilson on this
subject are corroborated by other witnesses. Indeed, nearly all
those competent to speak on the subject state or admit that the
process of decomposing fats into glycerine and fat acids by mixing
them with water, and subjecting the mixture to a high degree of
heat under a pressure sufficient to prevent the conversion of the
water into steam, was not known in the arts prior to Tilghman's
discovery. The testimony of some experts to the contrary is based
upon their construction of certain patents and publications
produced in evidence, the most important of which have already been
adverted to.
The question then arises has Tilghman secured the exclusive
right to the process of which he was thus the inventor?
Page 102 U. S. 718
An examination of the patent itself, which the preceding remarks
will enable us better to understand, will show, we think, that it
was intended to and does cover and secure to the patentee the
general process which has been described, although only one
particular method of applying and using it is pointed out.
The specification describes he invention as follows:
"My invention consists of a process for producing free fat acids
and solution of glycerine from those fatty and oily bodies of
animal and vegetable origin which contain glycerine as their base.
For this purpose, I subject these fatty or oily bodies to the
action of water at a high temperature and pressure, so as to cause
the elements of those bodies to combine with water, and thereby
obtain at the same time free fat acids and solution of glycerine. I
mix the fatty body to the operated upon with from a third to a half
of its bulk of water, and the mixture may be placed in any
convenient vessel in which it can be heated to the melting point of
lead, until the operation is complete. The vessel must be closed
and of great strength so that the requisite amount of pressure may
be applied to prevent the conversion of the water into steam."
"The process may be performed more rapidly and also continuously
by causing the mixture of fatty matter and water to pass through a
tube or continuous channel, heated to the temperature already
mentioned, the requisite pressure for preventing the conversion of
water into steam being applied during the process, and this I
believe is the best mode of carrying my invention into effect. In
the drawing hereunto annexed are shown figures of an apparatus for
performing this process speedily and continuously, but which
apparatus I do not intend to claim as any part of my
invention."
The specification then goes on to describe, by the aid of the
drawing referred to, the particular device mentioned. But it is
evident, and indeed is expressly announced, that the process
claimed does not have reference to this particular device, for the
apparatus described was well known, being similar to that used for
producing the hot blast and for heating water for the purpose of
warming houses. It consists of a coil of iron pipe, or other
metallic tubing, erected in an over or furnace, where it can be
subjected to a high degree of heat, and through this pipe the
mixture (of nearly equal parts of fat and water), made
Page 102 U. S. 719
into an emulsion in a separate vessel by means of a rapidly
vibrating piston, or dasher, is impelled by a force pump in a
nearly continuous current with such regulated velocity as to
subject it to the heat of the furnace for a proper length of time
to produce the desired result, which time, when the furnace is
heated to the temperature of 612� Fah., is only about ten minutes.
The fat and water are kept from separating by the vertical position
of the tubes as well as by the constant movement of the current,
and are prevented from being converted into steam by weighting the
exit valve by which the product is discharged into the receiving
vessel, so that none of it can escape except as it is expelled by
the pulsations produced by the working of the force pump. Before
arriving at the exit valve, the pipe is passed, in a second coil,
through an exterior vessel filled with water, by which the
temperature of the product is reduced. After the product is
discharged into the receiving vessel, it is allowed to stand and
cool until the glycerine settles to the bottom and separates itself
from the fat acids. The latter are then subjected to washing and
hydraulic pressure in the usual way.
After describing this apparatus, it is added:
"Although the decomposition of the neutral fats by water takes
place with great quickness at the proper heat, yet I prefer that
the pump should be worked at such a rate, in proportion to the
length or capacity of the heating tubes, that the mixture, while
flowing through them, should be maintained at the desired
temperature for ten minutes before it passes into the refrigerator
or cooling part of the apparatus."
It is evident that the passing of the mixture of fat and water
through a heated coil of pipe standing in a furnace is only one of
several ways in which the process may be applied. The patentee
suggests it as what he conceived to be the best way, apparently
because the result is produced with great rapidity and
completeness. But other forms of apparatus, known and in public use
at the time, can as well be employed without changing the process.
A common digester or boiler can evidently be so used, provided
proper means are employed to keep up the constant admixture of the
water and fat, which
Page 102 U. S. 720
is a
sine qua non in the operation. Tilghman himself,
as we have seen, often used such digesters in making his
experiments before applying for his patent, and, in putting up
machinery for his licensees after his patent was obtained, he did
the same thing when the parties desired it. Yet surely the identity
of the process was not changed by thus changing the form of
apparatus. No great amount of invention was required to adapt
different forms of well known apparatus to the application of the
process. The principal difficulty would be in providing an internal
arrangement in the boiler, or digester, for successfully keeping up
the intimate commixture of the fat and water. It is evident that
this could be accomplished by means of revolving reels armed with
buckets, or of a force-pump constantly transferring the heavy
stratum of water from the bottom of the mass to the top, aided by
horizontal diaphragms partially sectionizing the digester. These
devices were resorted to by Tilghman and others when they used a
boiler instead of a coil of pipe.
Whilst Tilghman in his patent recommends the high degree of heat
named, he does not confine himself to that. It had been fully
developed in his experiments, and was well known to him, that a
lower degree of heat could be employed by taking longer time to
perform the operation, and this would be necessary when boilers, or
digesters, of considerable size were used instead of the coil of
pipe on account of the decreasing power of large vessels to resist
the internal pressure. The specification, after describing the use
of a metallic coil of pipe, proceeds to add:
"The melting point of lead has been mentioned as the proper heat
to be used in this operation, because it has been found to give
good results. But the change of fatty matters into fat acid and
glycerine takes place with some materials (such as palm oil) at or
below the melting point of bismuth [510� Fah.]; yet the heat has
been carried considerably above the melting point of lead without
any apparent injury, and the decomposing action of the water
becomes more powerful as the heat is increased. By starting the
apparatus at a low heat and gradually increasing it, the
temperature giving products most suitable to the intended
application of the fatty body employed can easily be determined.
"
Page 102 U. S. 721
Now when we find it stated, as we do in this specification, that
the patentee subjects "fatty or oily bodies to the action of water
at a high temperature and pressure, so as to cause the elements of
those bodies to combine with water," that "the mixture may be
placed in any convenient vessel in which it can be heated to the
melting point of lead, until the operation is complete," that "the
vessel must be closed and of great strength, so that the requisite
amount of pressure may be applied to prevent the conversion of the
water into steam," that "the decomposition of the neutral fats by
water takes place with great quickness at the proper heat," that
"the melting point of lead has been mentioned as the proper heat to
be used in this operation, because it has been found to give good
results," that "the change of fatty matters into fat acid and
glycerine takes place with some materials at or below the melting
point of bismuth," that "the decomposing action of water becomes
more powerful as the heat is increased," that
"by starting the apparatus at a low heat, and gradually
increasing it, the temperature giving products most suitable to the
intended application of the fatty body employed can easily be
determined,"
and when we then find that the patentee categorically claims, in
general terms, as his invention "
the manufacturing of fat acids
and glycerine from fatty bodies by the action of water at a high
temperature and pressure," and being satisfied that he was in
fact the inventor of the general process described and bodied forth
in the specification -- how can we, by any fair rule of
construction, circumscribe this claim in such a manner as that it
shall only cover the process when applied in the use of a coil of
pipe heated to 612� Fahrenheit? Or, if we allow it to embrace any
"convenient vessel," and do not confine it to a coil of pipe, how
can we confine it to a particular degree of heat? What did Tilghman
discover? And what did he, in terms, claim by his patent? He
discovered that fat can be dissolved into its constituent elements
by the use of water alone under a high degree of heat and pressure,
and he patented the process of "manufacturing fat acids and
glycerine from fatty bodies by the action of water at a high
temperature and pressure." Had the process been known and used
before, and not been Tilghman's invention, he could not then have
claimed anything more than the
Page 102 U. S. 722
particular apparatus described in his patent; but being the
inventor of the process, as we are satisfied was the fact, he was
entitled to claim it in the manner he did.
That a patent can be granted for a process there can be no
doubt. The patent law is not confined to new machines and new
compositions of matter, but extends to any new and useful art or
manufacture. A manufacturing process is clearly an art within the
meaning of the law. Goodyear's patent was for a process -- namely
the process of vulcanizing india rubber by subjecting it to a high
degree of heat when mixed with sulphur and a mineral salt. The
apparatus for performing the process was not patented, and was not
material. The patent pointed out how the process could be effected,
and that was deemed sufficient. Neilson's patent was for the
process of applying the hot blast to furnaces by forcing the blast
through a vessel or receptacle situated between the blowing
apparatus and the furnace and heated to a red heat, the form of the
heated vessel being stated by the patent to be immaterial. These
patents were sustained after the strictest scrutiny and against the
strongest opposition.
On the subject of patents for processes, Mr. Justice Grier, in
delivering the opinion of this Court in
Corning v. Burden,
said:
"A process
eo nomine is not made the subject of a
patent in our act of Congress. It is included under the general
term, 'useful art.' An art may require one or more processes in
order to produce a certain result or manufacture. The term
'machine' includes every mechanical device or combination of
mechanical powers and devices to perform some function or to
produce a certain effect or result. But where the result or effect
is produced by chemical action, by the operation or application of
some element or power of nature, or of one substance to another,
such modes, methods, or operations are called processes. A new
process is usually the result of a discovery; a machine of
invention. The arts of tanning, dyeing, making waterproof cloth,
vulcanizing india rubber, smelting ores, and numerous others, are
usually carried on by processes, as distinguished from machines.
One may discover a new and useful improvement in the process of
tanning, dyeing, &c., irrespective of any particular form of
machinery or mechanical device. And another
Page 102 U. S. 723
may invent a labor saving machine, by which the operation or
process may be performed, and each may be entitled to his patent.
As, for instance, A. has discovered that by exposing india rubber
to a certain degree of heat, in mixture or connection with certain
metallic salts, he can produce a valuable product or manufacture;
he is entitled to a patent for his discovery, as a process or
improvement in the art irrespective of any machine or mechanical
device. B., on the contrary, may invent a new furnace, or stove, or
steam apparatus, by which this process may be carried on with much
saving of labor and expense of fuel, and he will be entitled to a
patent for his machine as an improvement in the art."
56 U. S. 15 How.
252,
56 U. S.
267.
Neilson's patent above referred to had some features very
similar to those of Tilghman's. The strong objection urged against
the latter is that the particular apparatus described in the
specification is not that which is generally used and that it
cannot be used with much profit or success in large manufacturing
operations, whereas the slower method of dissolving fats in a
common boiler, or digester, at a lower temperature even than that
of melting bismuth, which is not described in the specification, is
the one which is generally adopted. Precisely this circumstance
existed in reference to the patent of Neilson. The specification
directed that the blast or current of air produced by the blowing
apparatus should be passed into an air vessel or receptacle heated
to a red heat, and from thence into the furnace. Then, after
stating that the air vessel or receptacle should be increased in
size according to the size of the forge or furnace to be supplied,
the specification adds: "The form or shape of the vessel or
receptacle is immaterial to the effect, and may be adapted to the
local circumstances or situation." Now the most simple and natural
form of an air vessel, for heating the blast, as here directed,
would be a box or chamber, or a cylindrical vessel; but it turned
out in practice that a receptacle of this kind would answer the
purpose but very imperfectly, and that the best and most useful
method was to heat the blast in a series of tubes placed in a
heated oven. This was held to be no ground for invalidating the
patent or for preventing it from covering intermediate tubes as
well as an intermediate box or chamber, the jury being of
Page 102 U. S. 724
opinion that a man of ordinary skill and knowledge in the
construction of blowing and air heating apparatus would be able,
from the information contained in the specification, to erect a
machine which would answer some beneficial purpose in the
application of the process, and would not be misled and prevented
from so doing by the declaration that the form or shape of the
vessel or receptacle was immaterial to the effect. In this view of
the subject the patent was sustained after very great
consideration.
Some question has, indeed, been made whether Neilson's patent
was sustained as a patent for a process. The Court of Exchequer, in
reviewing the proceedings at the trial and answering the objection
that it was a patent for a principle, said:
"It is very difficult to distinguish it from the specification
of a patent for a principle, and this at first created in the minds
of some of the court much difficulty; but after full consideration,
we think that the plaintiff does not merely claim a principle, but
a machine embodying a principle, and a very valuable one. We think
the case must be considered as if, the principle being well known,
the plaintiff had first invented a mode of applying it by a
mechanical apparatus to furnaces, and his invention consists in
this -- by interposing a receptacle for heated air between the
blowing apparatus and the furnace. In this receptacle he directs
the air to be heated by the application of heat externally to the
receptacle, and thus he accomplishes the object of applying the
blast, which was before of cold air, in a heated state to the
furnace."
Web.P.C. 275, 371.
In this passage, we think that the Court of Exchequer (who spoke
through Baron Parke) drew the true distinction between a mere
principle, as the subject of a patent, and a process by which a
principle is applied to effect a useful result. That a hot blast is
better than a cold blast for smelting iron in a furnace was the
principle or scientific fact discovered by Neilson, and yet, being
nothing but a principle, he could not have a patent for that. But
having invented and practically exemplified a process for utilizing
this principle, namely, that of heating the blast in a receptacle
between the blowing apparatus and the furnace, he was entitled to a
patent for that process, although he did not distinctly point out
all the forms of apparatus
Page 102 U. S. 725
by which the process might be applied, having nevertheless
pointed out a particular apparatus for that purpose and having thus
shown that the process could be practically and usefully applied.
Another person might invent a better apparatus for applying the
process than that pointed out by Neilson, and might obtain a patent
for such improved apparatus, but he could not use the process
without a license from Neilson. His improved apparatus would, in
this respect, stand in a relation to the process analogous to that
which an improvement on a patented machine bears to the machine
itself.
That Neilson's patent was regarded as for a process is apparent
from what is said by the judges who had it under consideration.
Thus, Baron Parke at the trial had said:
"The specification and patent together make it clear what the
discovery was: it was the introduction of hot air by means of
heating it before it was introduced into the furnace, between the
blowing apparatus and the furnace."
Web.P.C. 275, 312. And when the matter came before the House of
Lords, after a trial in Scotland, Lord Campbell said:
"After the construction first put upon it [the patent] by the
learned judges of the Court of Exchequer, sanctioned by the high
authority of my noble and learned friend now upon the woolsack,
when presiding in the Court of Chancery, I think the patent must be
taken to extend to all machines, of whatever construction, whereby
the air is heated intermediately between the blowing apparatus and
the blast furnace. That being so, the learned judge was perfectly
justified in telling the jury that it was unnecessary for them to
compare one apparatus with another because, confessedly, that
system of conduit pipes was a mode of heating air by an
intermediate vessel between the blowing apparatus and the blast
furnace, and, therefore, it was an infraction of the patent."
Id., 715.
This case of the hot blast was commented upon in the great case
of
O'Reilly v. Morse, and is there recognized and approved
in the opinion of this court delivered by Chief Justice Taney.
After quoting the remarks of Baron Parke in the Court of Exchequer
cited above, the Chief Justice says:
"We see nothing in this opinion differing in any degree from the
familiar principles of law applicable to patent cases. Neilson
claimed
Page 102 U. S. 726
no particular mode of constructing the receptacle or of heating
it. He pointed out the manner in which it might be done, but
admitted that it might also be done in a variety of ways, and at a
higher or lower temperature, and that all of them would produce the
effect in a greater or less degree, provided the air was heated by
passing through a heated receptacle. . . . Whoever therefore used
this method of throwing hot air into the furnace used the process
he had invented, and thereby infringed his patent although the form
of the receptacle or the mechanical arrangements for heating it
might be different from those described by the patentee. For
whatever form was adopted for the receptacle, or whatever
mechanical arrangements were made for heating it, the effect would
be produced in a greater or less degree if the heated receptacle
was placed between the blower and the furnace, and the current of
air passed through it. . . . The patent was supported because he
[Neilson] had invented a mechanical apparatus by which a current of
hot air, instead of cold, could be thrown in. And this new method
was protected by the patent. The interposition of a heated
receptacle in any form was the novelty he invented."
56 U. S. 15 How. 62,
56 U. S.
115-116.
We have quoted these remarks of the Chief Justice more fully
because they show most clearly that he put the same construction
upon Neilson's patent that was put upon it by Lord Campbell, and
that he fully acquiesced in the legality and validity of a patent
for a process. Yet it has been supposed that the decision in
O'Reilly v. Morse was adverse to patents for mere
processes. The mistake has undoubtedly arisen from confounding a
patent for a process with a patent for a mere principle. We think
that a careful examination of the judgment in that case will show
that nothing adverse to patents for processes is contained in it.
The eighth claim of Morse's patent was held to be invalid, because
it was regarded by the court as being not for a process, but for a
mere principle. It amounted to this -- namely, a claim of the
exclusive right to the use of electromagnetism as a motive power
for making intelligible marks at a distance -- that is, a claim to
the exclusive use of one of the powers of nature for a particular
purpose. It was not a claim of any particular machinery, nor a
claim of any particular
Page 102 U. S. 727
process for utilizing the power, but a claim of the power itself
-- a claim put forward on the ground that the patentee was the
first to discover that it could be thus employed. This claim the
Court held could not be sustained.
That this was the true ground of the decision will be manifest
from the following observations of the Chief Justice in the opinion
already quoted from. He says:
"He [Morse] claims the exclusive right to every improvement
where the motive power is the electric or galvanic current, and the
result is the marking or printing intelligible characters, signs,
or letters at a distance. If this claim can be maintained, it
matters not by what process or machinery the result is
accomplished. For aught that we now know, some future inventor, in
the onward march of science, may discover a mode of writing or
printing at a distance by means of the electric or galvanic current
without using any part of the process or combination set forth in
the plaintiff's specification. . . . In fine, he claims an
exclusive right to use a manner and process which he has not
described, and indeed had not invented, and therefore could not
describe when he obtained his patent. The Court is of opinion that
the claim is too broad, and not warranted by law. . . . It is the
high praise of Professor Morse that he has been able by a new
combination of known powers, of which electromagnetism is one, to
discover a method by which intelligible marks or signs may be
printed at a distance. And for the method or process thus
discovered he is entitled to a patent. But he has not discovered
that the electromagnetic current, used as a motive power, in any
other method and with any other combinations, will do as well."
After reviewing the statutes and decisions bearing upon the
subject, the Chief Justice makes a summary conclusion of the whole
matter, as follows:
"Whoever discovers that a certain useful result will be produced
in any art, machine, manufacture, or composition of matter by the
use of certain means is entitled to a patent for it, provided he
specifies the means he uses in a manner so full and exact that any
one skilled in the science to which it appertains can, by using the
means he specifies, without any addition to or subtraction from
them, produce precisely the result he describes. And if this cannot
be done by the means he describes, the patent
Page 102 U. S. 728
is void. And if it can be done, then the patent confers on him
the exclusive right to use the means he specifies to produce the
result or effect he describes, and nothing more. And it makes no
difference in this respect whether the effect is produced by
chemical agency or combination, or by the application of
discoveries or principles in natural philosophy, known or unknown
before his invention, or by machinery acting altogether upon
mechanical principles. In either case he must describe the manner
or process as above mentioned and the end it accomplishes. And
anyone may lawfully accomplish the same end without infringing the
patent if he uses means substantially different from those
described."
Id., 56 U. S.
119.
It seems to us that this clear and exact summary of the law
affords the key to almost every case that can arise.
"Whoever discovers that a certain useful result will be produced
in any art by the use of certain means is entitled to a patent for
it, provided he specifies the means."
But everything turns on the force and meaning of the word
"means." It is very certain that the means need not be a machine,
or an apparatus; it may, as the Court says, be a process. A machine
is a thing. A process is an act or a mode of acting. The one is
visible to the eye -- an object of perpetual observation. The other
is a conception of the mind, seen only by its effects when being
executed or performed. Either may be the means of producing a
useful result. The mixing of certain substances together or the
heating of a substance to a certain temperature is a process. If
the mode of doing it or the apparatus in or by which it may be done
is sufficiently obvious to suggest itself to a person skilled in
the particular art, it is enough, in the patent, to point out the
process to be performed, without giving supererogatory directions
as to the apparatus or method to be employed. If the mode of
applying the process is not obvious, then a description of a
particular mode by which it may be applied is sufficient. There is
then a description of the process and of one practical mode in
which it may be applied. Perhaps the process is susceptible of
being applied in many modes and by the use of many forms of
apparatus. The inventor is not bound to describe them all in order
to secure to himself the exclusive right to the process if he is
really its inventor or discoverer.
Page 102 U. S. 729
But he must describe some particular mode or some apparatus by
which the process can be applied with at least some beneficial
result in order to show that it is capable of being exhibited and
performed in actual experience.
Let us apply these principles to the present cause. In the first
place, the claim of the patent is not for a mere principle. The
chemical principle or scientific fact upon which it is founded is
that the elements of neutral fat require to be severally united
with an atomic equivalent of water in order to separate from each
other and become free. This chemical fact was not discovered by
Tilghman. He only claims to have invented a particular mode of
bringing about the desired chemical union between the fatty
elements and water. He does not claim every mode of accomplishing
this result. He does not claim the lime saponification process, nor
the sulphuric acid distillation process, and if, as contended, the
result was accomplished by Dubrunfaut, Wilson, and Scharling by
means of steam distillation, he does not claim that process. He
only claims the process of subjecting to a high degree of heat a
mixture continually kept up of nearly equal quantities of fat and
water in a convenient vessel strong enough to resist the effort of
the mixture to convert itself into steam. This is most certainly a
process. It is clearly pointed out in the specification, and one
particular mode of applying it and carrying it into effect is
described in detail. But it is not the particular apparatus
described which Tilghman desires to secure by his patent. Having
pointed out the process and suggested a particular mode of applying
it, he claims as his invention "
the manufacturing of fat acids
and glycerine from fatty bodies by the action of water at a high
temperature and pressure." The true construction of this claim
is to be sought by comparing it, as have already done, with the
context of the specification; with the statement of the patentee
that his
"invention consists of a process for producing free fat acids
and solution of glycerine from those fatty and oily bodies of
animal and vegetable origin, which contain glycerine as a
base;"
that
"for this purpose, he subjects these fatty and oil bodies to the
action of water at a high temperature and pressure, so as to cause
the elements of those bodies to combine with water and thereby
obtain at the same time
Page 102 U. S. 730
free fat acids and solution of glycerine;"
that he
"mixes the fatty body to be operated upon with from a third to a
half of its bulk of water, and the mixture may be placed in any
convenient vessel in which it can be heated to the melting point of
lead"
[which is afterwards explained to be only desirable for a quick
result, not essential]; that "the vessel must be closed and of
great strength, so that the requisite amount of pressure may be
applied to prevent the conversion of the water into steam." This is
the process which the patentee claims to have invented, and this
description of it gives the proper construction and qualification
to the claim.
It is objected that the particular apparatus described in the
patent for carrying the process into effect cannot be operated to
produce any useful result. We have examined the evidence on this
point, and are satisfied that it shows the objection to be
unfounded. A recapitulation of this evidence is not necessary. The
testimony of Tilghman himself, of Professor Booth, and of Mr.
Wilson is directly to the point.
It only remains that we should express our views on the question
of infringement. The defendants advance several reasons for the
purpose of showing that their process does not conflict with that
of Tilghman. First, because they do not use the apparatus described
in the complainant's patent, but use a boiler in which the charge
of fat and other materials is placed and heated, and do not mix the
fat and water in the manner pointed out in the specification of the
patent, but, on the contrary, have inserted in the boiler a pump
which forces the water as it settles to the bottom upwards to the
top of the mass and pours it upon the upper surface, whence it
again finds its way down through the fat, thus keeping up a
constant mixture. It is unnecessary to add anything further on the
subject of the form of the apparatus used. The patentee is not
confined to a metallic coil of pipe heated in a furnace, but his
patent extends to and embraces any convenient vessel for holding
the mixture which is strong enough to sustain the pressure
necessary to prevent the water from being converted into steam. The
defendants use such a vessel, and use it for the purpose indicated
and pointed out in the patent. The vessel which they use has the
requisite strength to prevent the water from
Page 102 U. S. 731
being converted into steam, and does effect that object. And as
to the defendants' using a different method from that suggested in
the patent for keeping up the mixture of fat and water, that is of
no consequence. The keeping up of the mixture is the important
thing. That is a necessary part of the process. They employ such a
device for effecting this as is adapted to the form of vessel in
which they heat the material. Using a boiler instead of a coil of
pipe for this purpose, they are obliged to employ an additional or
modified means for keeping up the mixture. They only employ such
means as, in view of the change adopted in the form of the heating
apparatus, and of the known appliances in use in analogous
processes, would naturally suggest themselves to a mechanic skilled
in the art. Or, if the mode of effecting the continued mixture
adopted by the defendants should be deemed a new and useful
improvement, they might perhaps have a patent for that peculiar
device without being entitled to use Tilghman's process, on which
it is but an improvement.
Another ground on which the defendants argue that they do not
infringe the patent is that they do not, in their process, use
water alone in admixture with fat, but use also some portion of
lime; that they formerly used seven percent of lime, and now use
four percent. But they do not use lime in the manner and to the
extent in which it is used for dissolving fats by the saponifying
process. That requires twelve or fourteen percent. Even if the
saponifying process partly takes place, they use Tilghman's process
for effecting the balance of the operation. They use water in
admixture with fat, heated to a high degree, far above the boiling
point, and yet subjected to such pressure as to prevent the water
from being converted into steam, and though they may also use other
things at the same time, which other things may facilitate the
operation or render a less degree of heat necessary than would be
required when water alone is used, and thus actually improve the
process of Tilghman, yet this process is included in their
operation and forms the basis of it. It is idle, therefore, to say
that they do not infringe Tilghman's patent. It is unnecessary to
determine what precise part the lime used by the defendants plays
in their process -- whether, as the complainant
Page 102 U. S. 732
contends, it saponifies the fat to a certain extent, leaving the
remainder to be acted upon by the water alone purely after the
process of Tilghman, or whether, as the defendants contend, the
lime produces a more perfect and active commixture of the fat and
water, or predisposes the fat to unite with the requisite elements
of water necessary for producing glycerine and the fat acids -- in
either case, the process of Tilghman, modified or unmodified by the
supposed improvement, underlies the operation performed in the
defendants' boilers.
Another ground assumed by the defendants to avoid the charge of
infringement is that they do not heat the mixed mass in the manner
pointed out in Tilghman's specification, but, instead of heating
the containing vessel by an outside application of heat, they heat
the contents by the introduction of superheated steam. But we think
that this does not alter the essential character of the process.
The heating by steam is clearly an equivalent method to that of
heating by an external fire. The patent does not prescribe any
particular method of applying the heat except when using the pipe
and coil apparatus described in the specification, and even in the
use of this apparatus, the outward application of the heat to the
pipe is suggested incidentally and as a matter of convenience,
rather than as an essential requisite. The patentee showed one
method in which the heat could be applied. That was all that was
necessary for him to do. If it could be applied in any number of
different methods, it would not affect the validity of the patent
as a patent for a process. The method of heating the mixture by the
introduction of steam may be attended with some beneficial results
in producing an agitation or automatic circulation helpful to the
perfection of the admixture of the water and fat, and so far it may
be an improvement on heating from without. Suppose this to be so,
as before said, the introduction of an improvement gives no title
to use the primary invention upon which the improvement is
based.
Finally, the defendants argue that they only use a low degree of
heat and pressure compared with that pointed out by the patent,
namely, only about 310� Fah. instead of 612�. The precise degree of
heat, as we have seen, is not of the
Page 102 U. S. 733
essence of the patent. The specification only claims that a high
degree of heat such as would be sufficient to melt lead is most
effective and rapid in producing the desired result, but suggests a
trial of the apparatus employed with different degrees of heat so
as to ascertain that which is best for each particular kind of fat.
"By starting the apparatus," the language is,
"at a low heat, and gradually increasing it, the temperature
giving products most suitable to the intended application of the
fatty body employed can easily be determined."
It is probably true, as contended for by the defendants, that by
the use of a small portion of lime, the process can be performed
with less heat than if none is used. It may be an improvement to
use the lime for that purpose, but the process remains
substantially the same. The patent cannot be evaded in that way.
The matter may be stated thus: Tilghman discovers a process of
decomposing fats by mixing them with water and heating the mixture
to a high temperature under a pressure that prevents the formation
of steam. It is a new process, never known before. The defendants
seeing the utility of the process, and believing that they can use
a method somewhat similar without infringing Tilghman's patent, put
a little lime into the mixture, and find that it helps the
operation, and that they do not have to use so high a degree of
heat as would otherwise be necessary. Still the degree of heat
required is very high, at least a hundred degrees above the boiling
point, and a strong boiler or vessel is used in order to restrain
the water from rising into steam. Can a balder case be conceived of
an attempted evasion and a real infringement of a patent?
And as to the low degree of heat used in the operations of the
defendants, this must also be said: that with the reduction of the
temperature, the time of perfecting the operation is more than
proportionally increased. Tilghman was aware of this result, and
pointed it out in his patent. He expressly says: "The decomposing
action of the water becomes more powerful as the heat is
increased." What can be done in minutes by the application of a
very high degree of heat requires hours to do at the temperature
used by the defendant. But the process is still the same, and the
defendants fail to evade the patent.
Page 102 U. S. 734
We pass by the fact that the defendants first took a license
from the patentee, and under it and under his directions erected
substantially the same apparatus which they are yet using.
Receiving what they regarded as additional light, they refused to
continue the payment of a royalty, and put the complainant to his
legal remedy.
It is our opinion that the patent is for a process, that it is a
valid patent, and that the defendants infringe it.
We have considered the case entirely upon its merits. It is
unnecessary to bestow much discussion upon the technical objections
that have been raised. They have not been pressed in the argument,
and are probably not seriously relied on. One of them is that no
replication was filed in the case. To this it may be answered, that
the parties have throughout treated the case as though it were
regularly at issue. The various stipulations into which they have
entered with regard to the admission of evidence to be heard on the
trial of the cause are totally inconsistent with the idea that the
case was to be heard merely on bill and answer. Another objection
is that the patent was dated more than six months prior to the
filing of the application for it. But under the law then in force
(1854) with regard to the antedating of patents where a foreign
patent had been obtained, this was admissible. The sixth section of
the Act of March 3, 1839, entitled "An Act in addition to an act to
promote the progress of the useful arts," expressly declared
"That no person shall be debarred from receiving a patent for
any invention or discovery . . . by reason of the same having been
patented in a foreign country more than six months prior to his
application,
provided that the same shall not have been
introduced into public and common use in the United States prior to
the application for such patent,
and provided also that in
all cases every such patent shall be limited to the term of
fourteen years from the date or publication of such foreign letters
patent."
Now we know by the proceedings on the application in this case
that the attention of the Commissioner of Patents was expressly
called to the fact of the issuing of the English patent, and that
the question of the date of the patent in suit was submitted to and
considered by him. Under the laws then in force, he
Page 102 U. S. 735
determined that the patent ought to be antedated as of the date
of the English patent. It must be presumed that his decision was
right according to the facts of the case, at least until the
contrary is shown, and nothing has been shown to the contrary by
any evidence in the cause to which our attention has been
called.
The decree of the circuit court will be reversed, and the cause
remanded with directions to enter a decree in conformity with this
opinion, and it is
So ordered.