Engraving upon Steel. 353 



Art. XVII. — JVofice of Mr. Jacob Perkinses Invention of 

 Engraving upon Steel. — Editor. 



The American public are already informed that Mr. 

 Perkins, has given to the, before, comparatively perish- 

 able labours of the engraver, a degree of perpetuity v^^hich 

 may well vie with that of bronze or marble. We allude 

 to his well known discovery of a method of engraving 

 upon steel. In an interview with Mr. Perkins, some years 

 since, we were informed by him, that his steel plates, after 

 being duly prepared, were, by a particular process, car- 

 ried on by the aid of fire, decarbonized^ as (if we do not 

 misremember) he termed the operation. The result, at any 

 rate, was to soften the steel, so that it would admit of the 

 easy application of the graver. The design being made, 

 the plate goes through another fire process, by which it is 

 hardened to a high degree; and then the work becomes so 

 permanent, that the plate may be passed through the rolling 

 press to an almost indefinite extent, without undergoing any 

 material wear. 



We have just received, from Mr. Perkins, (now in Lon- 

 don,) s. planisphere of the " solar system ; shewing the orb- 

 its of the primary planets,* transferred to the plane of the 

 ecliptic, with the place of aphelion ; and exhibiting, also, 

 the satellites, the ring of Saturn, some of the comets and 

 their orbits, the ecliptic and its constellations, &£c. This 

 plate, executed on steel, and published by Perkins, Fairman 

 and Heath, is nine inches and three-fourths, by eight and 

 three-fourths; it was drawn and engraved by Lowry, whose 

 reputation is well known in this country, and is a beautiful, 

 and — for its particular object — a perfect thing. It is a fine 

 engraving; and the lines and shades are sufficiently delicate 

 to evince that this mode of engraving is susceptible of great 

 precision. Upon the margin of the plate, there is written, 



depress of pressure should be examined. For small pressures, the usual law 

 of elastic bodies, when made to undergo slight variations of form, viz. that 

 the variation of bulk is proportional to the compressing force, may be re- 

 garded as sufficiently established by the experiments of Canton and Oersted. 

 But farther experiments are wanting, to ascertain whether it continues to 

 hold true for pressures of several hundred atmospheres. 



* Including those of the new discovered ones, Vesta, Juno, Ceres and 

 Pallas, whose orbits are all included between those of Mars and Jupiter. 



Vol. IIT....N0. 2. 45 



