In Equity. On final hearing.

Gifford & Bull, for complainant.

Harry Van Ness Phillip, N. A. Acker, and W. F. Booth, for defendant.

LANNING, District Judge. The bill charges the defendant with conjoint infringement of claim 5 of patent No. 439,684, granted November 4, 1890, to N. W. Pratt, and the only claim of patent No. 595,852, granted December 21, 1897, to W. D. Hoxie. Each of the patents relates to improvements in steam-boilers and each of them is now owned by the complainant. Claim 5 of the Pratt patent is as follows:

"In a sectional steam-boiler, the combination of the furnace, the groups of inclined generating-tubes in vertical succession, having combustion spaces between them, the group or groups adjacent the furnace being composed of tubes of comparatively large diameter located at uniform distances apart, the succeeding group or groups being composed of tubes of comparatively small diameter arranged in sub-groups or clusters, the intervening spaces of which are greater than the intervening spaces between the constituents of the clusters."

The claim of the Hoxie patent is as follows:

"In a sectional steam-boiler of the type described, the combination with the reversed inclined water-tubes of a transverse steam and water drum, located at the front of the boiler in the space above said tubes, as shown and described."

It will be observed that each of these claims relate to a "sectional steam-boiler." The defendant contends that its boiler is nonsectional, while the complainant insists that it is sectional. This is the first disputed point demanding consideration.

The testimony shows very clearly that the dispute arises from the fact that the witnesses for the complainant and those for the defendant do not adopt a common basis for their classification of boilers. The complainant's witnesses consider as sectional (1) any boiler in which the water, instead of being confined in one mass in a shell, is distributed amongst tubes which have a front header and a rear header each common to all the tubes; and (2) any boiler in which the water, instead of being confined in one mass in a shell, is distributed amongst tubes composed of separate groups, each group having a front header and a rear header common only to the tubes of that group. The defendant's witnesses insist that a sectional steam-boiler is only such an one as is built in sections; each section being composed of a group of tubes which have front and rear headers common only to the tubes of that group. The defendant's boiler is a water-tube boiler, and therefore, according to the complainant's witnesses, is sectional, but its front and rear headers are common to all the tubes, and, for this reason, the defendant's witnesses say it is nonsectional. We see, then, that the complainant's witnesses denominate as sectional any boiler whose water is divided into sections, while the defendant's witnesses denominate as sectional any boiler whose headers are divided into

sections. The complainant's classification is based on the treatment of the confined water; the defendant's classification is based on the mechanical construction of the boiler. There is authority for both uses of the term "sectional steam-boiler." The term originated, however, in the use which the complainant's witnesses make of it. This is admitted by the defendant's expert witness, Mr. William StuartSmith, who says:

"Terms once applied to any device possess a great deal of inertia, and are difficult to displace, even though they become misnomers. When the watertube type of boiler was first introduced, a hundred or more years ago, they were called 'sectional boilers' to distinguish the new type, and they remained so for many years under that name; but later, when the type became subdivided, it was readily seen that the term was a misnomer and by no means described fully the type. Therefore the new name, 'water-tube boiler,' was used instead and has become of general use, although, as I say, the inertia of a term renders the use of the term 'sectional' by many people still common. Nevertheless it is not correct."

Mr. Stuart-Smith's admission that the complainant's use of the term "sectional" is still common is corroborated by other proofs in the case. The complainant's two patents were granted in 1890 and 1897, and Prof. Hutton, in his work "The Mechanical Engineer of Power Plants" (edition of 1897), says:

"A sectional boiler is a steam generator in which the plan of a single enreloping shell to contain the water and steam is abandoned, and is replaced by that of a number of small generating vessels so joined together that the steam formed in all of these separate units or sections is delivered from a common disengagement surface into a common steam space. The sectional principle may be carried in a boiler of large capacity to the extent of subdividing the disengagement area, so that the steam from several such areas would be delivered into a common steam drum, from which it shall be withdrawn by the steam pipe."

Quotations from other standard authorities, and from cyclopædias and dictionaries, might be made to show that the use of the term "sectional steam-boiler," in the sense in which the complainant's witnesses have used it, is common in the literature on the subject of steam-boilers. The present duty is to ascertain the sense in which the term is used in the complainant's two patents.

The Pratt patent is entitled "Sectional Steam-Boiler." The opening words of the specification are:

have invented certain new

"Be it known that I, Nat. W. Pratt, and useful improvements in sectional steam-boilers, of which the following is a specification: The herein described water-tube boiler is especially adapted for marine service. The construction of the same embodies a supporting structure composed as far as possible of the pipes forming the water spaces of the boiler."

I think the term "water-tube boiler" was here used synonymously with "sectional steam-boiler," for these reasons: First, because at the time the patent was granted such use of the term was common; second, because the term "sectional steam-boiler," used in the title of the patent, and the term "sectional steam-boilers," used in the first sentence

of the specification, relate to a class of boilers no less comprehensive than the class referred to by the term "water-tube boiler," used in the second sentence of the specification, the defendant's construction being one which makes the term "water-tube boiler" more comprehensive than the term "sectional steam-boiler"; and, third, because the use of the term "water spaces," in the third sentence of the specification, shows that the patentee had in mind sectional divisions of the water, and not sectional divisions of the mechanical structure. The mere fact that in the subsequent portions of the specification a sectionalheaded boiler is described is not sufficient to justify the defendant's conclusion that the sectional steam-boilers referred to in the patent include only those boilers that have sectional headers.

The single claim of the Hoxie patent speaks of a combination "in a sectional steam-boiler of the type described." These words of the claim refer to the type of boiler described in the specification. That type is a water-tube boiler, with reversed inclined tubes and a transverse steam and water drum located at the front of the boiler in the space above the tubes. There is no suggestion in the specification that the headers are sectional or nonsectional. The language is sufficiently broad to include boilers having nonsectional, as well as those having sectional, headers. The defendant's counsel argue, however, that the drawing annexed to the patent shows headers that are sectional. This argument is based solely on the fact that the two headers shown in the drawing have sinuous ends. While it is not probable that a header common to all the tubes would have a sinuous end, the mere fact that the drawing shows such headers will no more justify a restrictive construction of the specification than if the drawing should show two headers whose ends were straight. If, because the drawing shows two headers with sinuous ends, the specification must be held to describe only a boiler with sectional headers, then if, for the present drawing, there be substituted one showing two headers with straight ends, the specification should be held to describe only a boiler with nonsectional headers. The plain language of the specification, sufficiently broad to describe both classes of boilers, cannot be thus restricted, and be held to be descriptive of a sectional steam-boiler or a nonsectional steamboiler, according as the annexed drawing may show headers with sinuous or with straight ends. The specification describes a "water-tube boiler." Such a boiler is commonly known as a "sectional steamboiler," and since there is nothing in the specification to indicate that the headers are necessarily sectional I think the words "sectional steamboiler of the type described," used in the claim, refer to a water-tube boiler, having sectional or nonsectional headers, whose parts are arranged in the manner described in the specification.

The next disputed point relates to the alleged infringement of the Pratt patent. The water tubes of the defendant's boiler are all inclined from the front upwardly to the rear of the boiler. In the Pratt patent the lower tubes are inclined from the front downwardly to the rear, and the upper tubes from the front upwardly to the rear, as shown in figure 2 of the drawings for a double boiler annexed to the patent, which is as follows:

The specification says:

"The headers are serpentine in form, connecting the water-tubes 25 in single vertical series in staggered succession, or connecting the water tubes 26 in single vertical series of sub-groups or clusters in a similar staggered relation."

This means that a certain number of the lower tubes 25 (not numbered in the above figure, but being the tubes inclined from the front downwardly to the rear) are connected with a section of the front header, and with a corresponding section of the rear header, in such a manner that the tubes thus connected are arranged over one another (that is, in single vertical series), in a zigzag or staggered course, and that a certain number of the subgroups of the upper tubes 26 (not numbered in the above figure, but being the tubes inclined from the front upwardly to the rear) are connected with a section of the front header, and with a corresponding section of the rear header, in such manner that the subgroups thus connected are arranged over one another (that is, in single vertical series), in a zigzag or staggered course. It will be observed that the lower tubes 25 and the upper tubes 26

are oppositely inclined, and the specification says that "the opposite inclinations of the successive groups of tubes promote the reverse circulation." This statement, it seems to me, makes it reasonably clear that "the groups of inclined generating tubes in vertical succession," mentioned in claim 5, mean the oppositely inclined tubes 25 and 26, and not the inclined tubes 26 alone. There is nothing in the specification or drawings intimating a purpose to use in a boiler a group or bank of tubes inclined only as the tubes 26 are inclined. The claim of a patent must be read in connection with its specification. When the whole of claim 5 is read, it is found to relate to the larger tubes adjacent to the furnace and also to subgroups of small tubes, which latter the specification shows are above the larger tubes, and oppositely inclined to the larger tubes for the purpose of promoting reverse circulation. Claim 5 is for a combination. It is utterly impossible to understand it without reference to the specification. That reference, I think, shows that the larger and the smaller tubes shall be oppositely inclined, notwithstanding no such statement is expressly made in the claim. As all the tubes in the defendant's boiler are inclined in one direction, the defendant does not use the combination described in claim 5 of the Pratt patent, and consequently, does not infringe it. The Hoxie patent presents a very different question. The only drawing annexed to it is shown on opposite page.

The specification and claim are not long and are quoted in full, with numerals inserted at the beginning of each sentence for the purpose of convenient reference:

"Be it known that I, William D. Hoxie, a citizen of the United States, residing at Brooklyn, in the county of Kings and state of New York, have invented a new and useful improvement in steam boilers, of which the following is a specification. [1] Heretofore in this type of boiler the inclined water-tubes were set at an acute angle with the vertical face or front of the boiler-in other words, were pitched downwardly from the front to the rear-the combustion-space within the furnace being highest at the front and lowest at the rear portion. [2] This arrangement of the inclined water-tubes also left a vacant vertical space above the rear end of the tubes. [3] The present invention consists in reversing the inclination of the water-tubes-that is, directing them upwardly from the front to the rear at an obtuse angle with the vertical face or front of the boiler-thus increasing the capacity of the combustion-chamber of the furnace at its rear part and transferring the vacant space above the tubes from the rear to the front of the boiler, and locating the steam and water drum at the front within this space, whereby it and its attachments are rendered more accessible and convenient for use and the whole structure made more compact. [4] Another great advantage in this reverse arrangement of the water-tubes is that they pitch downward toward the front of the boiler, which enables them and their spaces to be readily cleaned, removed, or repaired from directly within the fire-room. [5] In the accompanying drawing a side elevation, partly in section, of a boiler is shown embodying the improved arrangement. A, A, representing the vertical headers: B. the intermediate inclined water-tubes; C. the furnace with its door. C'. and D the steam and water drum with its water-gage, d, these parts constituting the main essential elements in the structure, that are only necessary to refer to herein as explanatory of the appended claim. [6] By the construction and relative arrangement of the parts above enumerated and illustrated in the drawing it will be observed that the combustion-chamber of the furnace is enlarged at its rear portion, which allows the gases to expand and give out their full heating effect as they pass to the inclined water-tubes which form