126 ANNUAL OF SCIENTIFIC DISCOVERY. 



engraving, or drawn upon a colored lithographic stone the only difference 

 being the accuracy and beauty of the impression. But this is not all. 

 The method just described is connected -with another invention, based 011 

 the typographic principle of combination and distribution, but in which 

 an alphabet of artistic forms is combined and distributed instead of 

 letters. 



THERMOGRAPHY. 



This is the designation bestowed by M. Felix Abate on a method lately 

 discovered by him for transferring figures and tracings, whether natural or 

 artificial, to wood, calico and paper, directly from the objects themselves, 

 provided these possess, or are capable 'of being converted into, plane 

 surfaces. This invention is an offshoot of the mode employed in Birming- 

 ham and Sheffield for transferring raised patterns, such as lace to metal, 

 by means of pressure ; but instead of this transfer of the figure from the 

 natural object, say a feather, to the soft metal, thence to an electro- 

 copper plate, and at last to the paper, M. Abate proposes to print directly 

 from the objects themselves, and has exhibited to the Society of Arts some 

 imitations of veneer and of inlaid work taken on sheets of wood, calico 

 and paper, and which he states were procured by the following process : 

 The sheet of veneer or inlaying to be copied is to be exposed for a few 

 minutes to the vapor of hydrochloric acid. The inventor names also 

 sulphuric acid vapors ; but this must be a mistake, this acid not emitting 

 fumes at common temperatures ; or it is to be damped with either of these 

 acids diluted, and the excess of moisture carefully wiped off. The sheet of 

 veneer is then laid upon one of calico or paper, and an impression struck off 

 by a common printing-press ; this impression remains invisible until, as 

 with many of the sympathetic inks, it is exposed to the action of heat, 

 which is to be applied immediately after the sheet is printed off, when a 

 perfect impression of all the marks, figures, and convoluted lines of the 

 veneer is instantaneously produced. This may be repeated for an almost 

 indefinite number of times, wetting the veneer occasionally -with the dilute 

 acid, without the impression growing fainter. The designs thus produced 

 all exhibit a general wood-like tint, most natural when oak, walnut, maple, 

 and the light- colored woods have been employed ; the darker woods, as 

 mahogany, rosewood, &c., may be printed on cloth or paper, dyed or 

 stained to a light shade of the ground color of the particular wood. 



These impressions show an inversion of tints in reference to the original 

 wood the light parts being dark, and vice versa ; but this does not 

 interfere with the general effect. Should, however, a true image be 

 desired, the inventor damps the wood-surface with a solution of ammonia, 

 and then prints on the cloth or paper previously wetted with the dilute 

 acid, and exposes to strong heat as before, when, he states, the eifect will 

 be a true representation of the wood. 



Tins process will undoubtedly prove useful in decoration, since it 



