Galvanifm.—Art of making Cutlery. tlj 



hydrogen is too ftrong, and the oxigen of the atmofphere could not unite with it in the 

 decompofition of the metal. The ammoniac merely took a flight blueifh colour, which 

 fliews that it had diflblved a portion of copper from the filver piece. 



We fee very clearly, from the refults which I have obtained from the fimple contafl of 

 the two metals, namely, the oxide and the faline cryftals, that the fenfations experienced 

 on the tongue, and on the eye, are the confequence of a chemical operation : and it there- 

 fore appears to me, that it is to thefe new. compounds, or their elements, that we are to 

 attribute that myRerious ftimulus, which produces convulfive motions of the animal fibre 

 in a great part, at leaft, of the phenomena of galvanifm. 



VI. 



Report concerning the Art of making fine Cutlery.—^, N. 



X HE fabrication of edge tools is one of the firft arts among men in every ftatc of fociety.. 

 Artizans are well aware of the neceflity, that the inftruments of their refpedtive trades 

 fhould be made to poffefs the qualities adapted to the operations by which they gain their 

 fubfiflence ; and among the various fub-divifions of labour, there is perhaps no material, 

 upon which the ikill and judgement of praftical men are more multifarioufly exercifed than 

 fleel. The makers of files, of chifliels, of planes, faws, and the infinite variety of knives, 

 all occupy their feveral departments feparate from each other, and poffefs their refpettive 

 degrees of celebrity among workmen, which are grounded on their knowledge of the 

 peculiar kinds of fleel, as well as the methods of working them, which are beft fuited 

 to the intended operations. Many of thefe methods are kept fecret; but in general the 

 philofophical enquirer will find the communications of operative men, to the full, as liberal 

 and open as the circumftances of the cafe may feem to warrant. Many manufa£turers have 

 no referve with regard to the manipulations of their art, and have the fpirit to affert their 

 claims to public encouragement, upon the open ground of the addrefs and integrity with 

 which they conduft their profeffional labours. 



Among the inflances of this kind which have occurred to me during a life of diligent 

 enquiry, I have lately been much gratified by the ready affiftance and communications of 

 Mr. Stodart of the Strand, which enable me at prefent to communicate nfiy own notion* 

 on the fubjeft of fine cutlery, with the advantage and fupport of his fuccefsful experience } 

 which I fhall proceed to do without farther preface. 



It appears to be at prefent generally agreed, that for all works which do not require 

 welding, caft fteel is preferable to any other. For fine cutlery it undoubtedly is. Mr.. 

 Stodart ufes thofe bars which are marked Huntfman, but does not fuppofe it to be of a 

 better quality than that of Walker, and other manufadturers. He complains, that it i?. 



much 



