Monce v. Adams. more obtuse, the cutter is found to operate to the best advantage. The cutter can be fitted to revolve upon a pin, or on solid journals at each end, which latter mode I prefer, and show the same in drawings. The frame, near one end, is provided with bearings for the journals, which journals should be a little shorter than the thickness of the sides of the frame, in order that, when the sides are placed against a straight edge or other gauge, the end of the journal shall not come in contact with such gauge. The handle, C, can be of any desired form, and secured to the frame in any proper manner. I construct said handle like the handle ordinarily used for a diamond tool. *** By my invention I produce a tool for cutting glass, which is equally convenient in use as an ordinary diamond, and can be sold at a large profit, for one-tenth of the usual cost of a diamond." The claim is as follows: "I do not claim simply a revolving cutter, but what I claim as new, and desire to secure by letters patent, is, 1. The cutter, A, constructed substantially as shown and described, and for the purposes set forth; 2. The combination of the cutter, A, frame, B, and handle, C, substantially as and for the purposes described." The drawings attached to the specification show that the instrument is a tiny steel revolving cutter or wheel, made as described in the specification, attached to a frame and handle, the whole resembling very much the glazier's diamond ordinarily in use. It is clearly proved that this instrument is exceedingly well adapted to the purpose for which it was designed; that very large quantities have been sold at a cheap rate; that it has superseded the use of all other steel glasscutters; and that it is an efficient and useful tool, while previous inventions have been failures. A glazier's diamond is sold at from $3 50 to $5 00, while this article is sold at fifty cents or less. The use of a tool for glass-cutting is thus brought within the reach of every householder. It is admitted, that the invention does not consist of a revolving cutter; and it is obvious that it does not consist in a revolving cutter of a high degree of hardness, for, "hardened" steel cutters Monce v. Adams. had been known previously to the date of the patent. The invention, then, so far as the cutter is concerned, must consist in its form-in the fact that the sides are made parallel, and then bevelled towards each other at an angle of about fortyfive degrees to the axis of the cutter, so as to meet about midway between the same, in a cutting edge. The sides, at the cutting edge, will, consequently, if they are at an angle of forty-five degrees to the axis of rotation, be at right angles to each other. As has been said, the object of the patentee was to make an economical substitute for the glazier's diamond, which should, if possible, possess the requisites which experience had shown were best adapted to successful glasscutting. In order to determine whether the utility and success of this invention depends upon any peculiarities in the form of the cutter, it is desirable to ascertain upon what depends the efficiency of the diamond. While almost any diamond will scratch or tear the surface of glass, it is a fact that the value and efficiency of a diamond to be used for the cutting or severing of glass, depends not merely on the hardness, but upon the form, of the cutting surface. Other gems than the diamond will successfully cut glass, provided they can be shaped into forms similar to those of the diamonds used for this purpose. Dr. Wollaston, in the Philosophical Transactions for 1816, thus explains the peculiarities required for the glazier's diamond: "In the natural diamond, there is this peculiarity, in those modifications of the crystals that are chosen for this purpose, that the surfaces are, in general, all curved, and, consequently, the meeting of any two of them presents a curvilinear edge. If the diamond is so placed, that the line of the intended cut is a tangent to this edge, near to its extremity, and if the two surfaces of the diamond laterally adjacent be equally inclined to the surface of the glass, then the conditions necessary for effecting a cut are complied with. The curvature is not considerable, and, consequently, the limits of inclination are very confined. If the handle be too much or too little elevated, the one extremity Monce v. Adams. of the curve will be made to bear irregularly upon the glass, and will plough a ragged groove, by pressure of its point. But, on the contrary, when the contact is duly formed, a simple fissure is effected, as if by lateral pressure of the adjacent surfaces of the diamond, diverted equally to each side. The effects of inequality in the lateral inclination of the faces of the diamond to the surface of the glass are different accord ing to the degree of inequality. If the difference be very small, the cut may still be clean, but, as the fissure is then not at right angles to the surface, the subsequent fracture is found inclined accordingly. When an attempt is made to cut with an inclination that deviates still more from the perpendicular, the glass is found superficially flawed out on that side to which the greater pressure was diverted, and the cut completely fails." Again, from the testimony given in this case it appears, that it is necessary, for practical use, as a glass-cutter, that the sides of the instrument should be bevelled towards each other at about a right angle, for two reasons: 1st. A more acute angle would not be sufficiently durable. 2d. Experience has shown that, in order to cut glass successfully, the cutting edges of the tool, whether of a diamond or of any other cutter, must be at a right angle to each other. This fact is also asserted by the authorities upon the subject. The reason why such an angle is necessary does not seem to be clearly explained. Hence, the requisites of the form of a tool best adapted to glass-cutting, are three-fold: 1st. The cutting edge should be curvilinear. 2d. The cutting edges should be at right angles to each other. 3d. The two surfaces of the diamond which are adjacent to the cutting edge should be equally inclined to the surface of the glass. The cutter should also be so placed in its frame as most easily to bring the cut which is to be made at right angles with the surface of the glass. Recurring, now, to the alleged invention, the sides of the cutter are made parallel and then bevelled towards each other at an angle of about forty-five degrees to the axis of the cutter, Monce v. Adams. so as to meet about midway, in a cutting edge. The conditions necessary to form a glazier's diamond are thus complied. with; for, by making the two sides of the cutter parallel for a short distance, and then bevelling them towards each other at an angle of forty-five degrees to the axis of rotation, till they meet, "the two surfaces" of the cutting instrument, laterally adjacent, are equally inclined to the surface of the glass." The frame being attached to the cutter in the precise way in which the handle is attached to the diamond, the inclination of the cut will naturally be at right angles to the surface of the glass, and the lateral pressure of the adjacent surface of the cutter is "diverted equally to each side." Furthermore, the sides, at the cutting edge, being at or near an angle of forty-five degrees to the axis of rotation, will be at or near an angle of ninety degrees to each other. Having thus ascertained wherein the peculiarity of the cutter consists, is this form a new invention of the patentee, or has it been anticipated by others? The respondent claims that this alleged invention is an instance of double use-the mere application of an old device to a new purpose. He introduces the patents of Charles Wilson, of March 13th, 1847, and April 10th, 1849, of Joseph E. Stanwood, of April 26th, 1859, and of A. H. Hook, of September 13th, 1864, to show, not only that the use of steel cutters for cutting hard substances was well known, but that the cutter in each of these patents was of a similar form with the one in the Monce patent. The first patent to Charles Wilson was for a mode of cutting stone or other like material, by means of a revolving cutter, operating in a described manner, and was particularly designed for the smoothing and finishing of grindstones. Whether the knives in Wilson's machine are able to cut glass or not is unknown. In either event, the particular form or shape of the knives or cutters was not a part of Wilson's machine, and, whether they were or were not accidentally bevelled at an angle of forty-five degrees, was an unrecognized circumstance, of no value or importance to his discovery. Monce v. Adams. The second patent of Wilson is entirely immaterial to the present case. The patent of Stanwood was for a revolving cutter, so operating upon gas or iron pipe, secured in place by a clamp or jaw, as to cut the pipe. Sometimes, one of the cutters, detached from the heavy frame in which it is placed, will cut or tear glass. Ordinarily, however, an instrument intended for cutting pipe cannot be successfully used upon glass. The requisites for successful pipe-cutting are very different from those for successful glass-cutting, and, consequently, it is only in exceptional cases that a gas-pipe cutter can be used upon glass. Such a cutter could never be made a practical substitute for a diamond. But, in this, as in the first Wilson patent, the invention which is the distinctive feature of the Monce patent is unknown and unrecognized. In the Stanwood device, the sides of the cutter may or may not be bevelled 'towards each other at a particular angle. The angles vary in different specimens of the article, sometimes exceeding, and sometimes being under, forty-five degrees. The Hook patent is for a paper-cutter. It is sufficient to say, that one of its sides is at right angles to the axis of rotation. The respondent also introduced the cutter attached to a book-binders' machine for cutting pasteboard, and claims that it has long been in use, and will cut glass. The pasteboard cutters exhibited upon the trial, did not cut glass readily or easily. The truth probably is, that such a cutter of unusual hardness will also sever glass, but those ordinarily and usually made will not answer this purpose. The sides of the pasteboard cutter are, apparently, but slightly inclined towards each other. Thus far, the well known principle relied upon by the respondent is inapplicable to the present case, inasmuch as it is untrue, that the distinctive feature of the patented article was used as a part of the cutters previously existing. The alleged invention of Monce was neither a part of the invention of previous patentees, nor was it a part of their machines, |