1893.] ^-^ ^ [Bache. 



detail to the production of a new tiling, an article that happened to be in 

 the market, an examiner decided against allowing a patent, upon the 

 ground that the man who had invented the incidentally used article had 

 invented it for all the possible uses to which it might in the future be ap- 

 plied ; an untenable proposition, easily disposed of upon appeal, by an ar- 

 gument that I made, supported, as witnesses, by Prof. Joseph Henry, Dr. 

 Henry Morton, Mr. J. E. Hiigard, and General Meade. 



The validity of patentable invention depends upon two factors, the 

 realization of an idea as embodied in an original apparatus. Thousands of 

 men since Daedalus have conceived of the practicability in various manners 

 of aerial navigation under the open skies, but the embodiment of the idea 

 still remains undemonstrated. The person who invented the gauze-wire 

 door for an oven certainly thereby made a step in advance towards culi- 

 nary aeration of the oven for meat, and therefore a step in the right direc- 

 tion towards the oxygenation of it, whatever may have been his intention 

 with reference to the result observable. But, even conceding his full 

 intention in that regard, and the incontestability of the result, the apparatus 

 is still a most imperfect one for securing the desirable end, so remote from 

 anything but embryonic function, that it may justly be regarded as simply 

 tentative in the right direction. When, moreover, we additionally con- 

 sider that patents issue under the characterization of " improvements " in 

 some designated category, containing thereby the implication that there 

 can be no absolutely new invention, it is impossible to see why the appa- 

 ratus which I submitted to the Patent Office of the United States does not 

 at least come under the designation of an improvement on the gauze-wire 

 door oven, of which my patent agents knew before they entered my appli- 

 cation for a ventilated oven (the records always being consulted pre- 

 viously), and therefore could not have thought barred my claim. 



If we are to concede that exposing the interior of an oven more or 

 less to circumambient air, of wluilever quality, and dependent for its 

 movement solely upon radiation, then any one who ever purposely left an 

 oven door ajar while meat was cooking in it, made to the wire-gauze door 

 an approximate invention. Everything leaks to air and water. If the 

 adoption of either method constitutes oxygenation of an interior, in the 

 sense in which it is here used, then it follows that every natural and arti- 

 ficial cavity on earth can be deemed aerated, even the receiver of an air- 

 pump, except one where there is no untraversed space in the cylinder, 

 secured by surrounding the piston by mercury, as in the air-pump of 

 Kravogl. Aerated and oxygenated, in a certain narrow sense, the oven 

 with the gauze-wire door may certainly be considered to be, but in the true 

 sense, which I had in view in my device, it cannot be considered effective. 

 Such an oven receives from the kitchen all the effete products floating in 

 the air. Its change of air, such as it is in amount, whatever it may be in 

 quality, is only owing to the erratic flux and reflux primarily set up by ra- 

 diation from the mouth of the oven. On the contrary, the device which I 

 presented for the purpose defined admits the purest outdoor air at com- 



I'KOC. AMER. THILOS. SOC. XXXI. 142. 2 O. PRINTED DEC. 7, 1893. 



