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Statement of the case.

prolonging the time of cooling, in connection with annealing wheels would, if rightly conceived, secure the desired end.

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It was in this state of the art and of its necessity that Whitney made a claim for what he called “ a new and useful improvement in the process of manufacturing cast-iron railroad wheels,” and on the 25th of April, 1848, obtained a patent for it, for fourteen years.

The specification in his patent was thus:

“My improvement consists in taking railroad wheels from the moulds in which they are ordinarily cast, as soon after being cast as they are sufficiently cool to be strong enough to move with safety, or before they have become so much cooled as to produce any considerable in berent strain between the thin and thick parts, and putting them in this state into a furnace or chamber that has been previously hcated to a temperature as bigh as tbat of the wheels when taken from the moulds. As soon as they are deposited in this furnace or chamber, the opening through which they have been passed is closed, and the temperature of the furnace or chamber, and its contents, gradually raised to a point a little below that at which fusion commences,

Statement of the case.

when all the avenues to and from the interior are closed, and the whole mass left to cool no faster than the heat it contains permeates through, and radiates from the exterior surface of the materials of which it is composed. By this process all parts of each wheel are raised to the same temperature, and the heat they contain can only pass off through the medium of the confined atmosphere that intervenes between them and the walls of the furnace or chamber; consequently, the thinnest and thickest parts cool and shrink simultaneously together, which relieves them from all inherent strain wbatever when cold.

“The figure below represents a vertical cross-section of the FURNACE or CHAMBER, wherein is shown a pile of wheels as they

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are placed to be annealed. The cover of the furnace, being movable, is raised when the wheels are put in, and then closed and covered with earth, to prevent the too rapid escape of the heat. The damper in the fue leading to the chimney is also closed, after the wheels are put into the furnace, and the opening in the lower wall stopped by an iron plato banked with eartb, which prevents the escape of the heat in that direction. *

* There were other drawings and descriptions, not given by the reporter.

Statement of the case.

“To beat this furnace, I have used anthracite cual, it requir. ing less than one-fourth of a ton to anneal two tons of whee18. The heat required to perform the process may, however, be obtained by the use of any other fuel that may be less expensive at the place where the process is to be performed; or the requisite beat may be taken in a suitable conduit from the furnace in which the metal is melted from which the wheels are made, after it has performed that office, to the chamber in which the annealing process is to be performed. In either case, however, the furnace or chamber must be made of such form, and have such appendages connected with it, as to enable the operator to control the quantity and intensity of the heat used by admitting more or less of it into the chamber, and of excluding it entirely..

“The advantages resulting from the process of prolonging the cooling and annealing, as above described, are that the wheels may be made much stronger, when made of the same weight, than they can be when cast and cooled in the ordinary manner; and railroad wheels, having any form of spokes, or disks connecting the rim and bub, if subjected to this process, will not require their hubs to be cast in sections, and the spaces

between the sections subsequently filled with some suitable inetal, and wrought bands put on to the hub.

“Wheels subjected to this process of cooling and annealing will be stronger without bands on their bubs than those of the same weight cast and cooled in the ordinary way, baring the wrought-iron bands on. In this way the original cost is diminished, and the wheels rendered more durable than they would be when made in any of the ways heretofore employed.

"I do not claim to be the inventor of annealing castings made of iron or other metal, when done in the ordinary way; nor do I claim to be the inventor of any particular form or kind of furnace, in which to perform the process. But what I do claim as my invention, and desire to secure by letters-patent, is the process of prolonging the time of cooling, in connection with annealing railroad wbeels, in the manner above described; that is to say, tbe taking them from the moulds in which they are cast, before they have become so much cooled as to produce such inherent strain on any part as to impair its ultimate strength, and immediately after being thus taken from the moulds, depositing them in a previously-beated furnace or

Statement of the case.

chamber, so constructed, of such materials, and subject to such control that the temperature of all parts of the wheels deposited therein, may be raised to the same point (say a little below that at which fusion commences), when they are allowed to cool so fast, and no faster, than is necessary for every part of each wheel to cool and shrink simultaneously together, and no one part before another."*

Whitney being in possession of his patent as already de. scribed, one Mowry, of Ohio, conceived that he too had made a valuable improvement in the same branch as White ney professed to have made one; and on the 7th of May, 1864, also obtained a patent. His specification, illustrated by a vertical cross-section of his furnace, says:

“My invention consists in the use of charcoal or other equiva- . lent substance, interlaid with the wheels in the annealing pits, in connection with the regulated admission of air, for the purpose of heating the wheels up to a proper temperature, prolonging the heat, and permitting them to cool in the course of a given time, gradually, as will be more particularly explained below.

“ The operation of my invention is as follows: A layer of charcoal baving been laid on the perforated bottom of the anDealing pit, the wheels, as they are turned out of the moulds red bot, are placed in the pits, with a layer of charcoal between each wheel, a layer of charcoal being laid on the uppermost wheel, and on this a perforated metal plate is laid.

“The charcoal, becoming now ignited by the hot wheels, the cover of pit is then laid on, and the damper opened so as to admit just sufficient air to effect the combustion of the contained charcoal, in the space of seventy-two hours, less or more, as may

* It may here be stated that, on the 7th of August. 1849, there was granted to one Murphy a patent (extended subsequently for seven years from the 7th of August, 1863) for a mode of cooling car-wheels, which consisted in en. casing and protecting from the air all parts of the wheels except the hubs, and causing a current of cold air, by means of connection with the main chimney, to pass through the hubs, thus retarding the cooling of the plates und speeding the coolirg of the hubs. This process, it will be observed, was the antithesis of Whitney's, the essence of which consisted in heating the wheels until all parts of them had attained the same degree of heat.

Statement of the case.

be found necessary for the annealing operation. The draft of air in the apparatus sbown on drawings, is from above down. ward, but it may, without affecting my invention, be from below upwards, by conveying the air from the horizontal flue, up through the pits, and through the aperture in cover, and from thence through flues, into the main shaft or chimney C; the result will be the same in both cases, and the adoption of one or the other plan will be äictated by convenience.”

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Under his patent Mowry employed a process of annealing such as it described; and Whitney thereupon filed a bill to enjoin him as an infringer. Mowry answered, denying infringement, alleging the invalidity of Whitney's patent for want of novelty and for want of utility,

Inasmuch as the said process would ruin anı destroy the hardness on the rim of the car-wheels, known as the chill, and thus greatly detract from the usefulness and durability of the wheels.

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