SEVERAL MECHANICAL INVENTIONS. 169 



inventors, whose names* I have brought (in former papers) 

 to the special notice of the Society, I have (in the present 

 one) aimed to place that of Jacob Perkins as a worthy con- 

 tributor to the advance of those branches of art to which 

 his original inventions have been applied. 



APPENDIX I. 



In tracing the progress of steel engraving, I had no 

 thought of giving an account of the life and general re- 

 searches of Mr. Perkins in the physical sciences, some of 

 them having been long ago published and duly appreciated. 

 Yet it may not be out of place here to refer to such of his 

 other discoveries as became suggestive of the many im- 

 provements since made in kindred branches of knowledge. 



His "Experiments on the Compressibility of Water," 

 made some time before he left America, were for ascertain- 

 ing the truth of the old Elorentine doctrine, that water was 

 a " non-elastic " body ; which doctrine, founded on the 

 Florentine experiments, was still taught in the schools and 

 elementary works, and generally accepted. But the " Per- 

 kins's experiments" clearly established the elastic nature 

 of water, and showed that it, like air, was compressible in 

 volume, directly as the compressing forces. At that time 

 Mr. Perkins fully believed this to be a new discovery, as 

 he had never heard of the experiments of Canton, made 

 some fifty years before. Though not strictly a " new dis- 

 covery," the experiments of Perkins were of high scien- 



* These are, (i) 'Robert Fulton, who first succeeded in " ^practical siQdim. 

 navigation." 



(2) William Eaton, inventor of the " self-acting mule." 



(3) John Heathcoat, inventor of lace-making. 



(4) Amos Whittemore, inventor of wire-card making. 



