444 



Mr. Mushet on the Immersion of Copper 



The following table would at first give additional facility in 

 changing the decimal scale into the present, and vice versa. 



Being desirous of giving publicity to the results of my in- 

 quiries on this subject, I have put them into the present form, 

 in the hope that you will be able to find for them a spare 

 page or two of your valuable scientific periodical. 

 I beg to remain, Gentlemen, 



Your obedient Servant, 

 His Majesty's Dockyard, c, t> 



Chathara/Feb. 4th, 1835. SaMUEL Read. 



LXXI. On the Immersion of Copper for Bolts and Ship- 

 sheathing in Muriatic Acidy as a Test of its Durability, By 

 David Mushet, Esq, 



T^HE durability of copper for bolts and ship-sheathing being 

 -■- an object of great national importance, and as there is 

 no better test of its resistance to waste than immersion in mu- 

 riatic acid, the following experiments, made thirteen years ago, 

 will, it is hoped, be found not uninteresting. 



Small quantities, presenting nearly equal surfaces of each of 

 the kinds of copper described in my last communication, p. 324, 

 namely, pure shotted copper of the quality from which brass 

 is made, and shots obtained from unrefined copper, were se- 

 parately immersed in equal weights of muriatic acid. The 

 immersion having been continued for forty-eight hours, the 

 acid was poured off, and the copper washed repeatedly and 



cimal money table for the term " half-pound ;" our accounts being kept in 

 regents, shillings, tenths, and cents, instead of halt-pounds, shillings, tenths, 

 and cents. For this suggestion I am indebted to a friend well known in 

 scientific circles, and to whom I have communicated the subject-matter of 

 this paper.— AfarcA Uth, 1835. S.R. 



