CHEMICAL SCIENCE. 209 



In reference to the above subject, we would add that Professor James C. 

 Booth, of Philadelphia, is now engaged, by the order of government, in an 

 extensive series of experiments on fusible alloys, and their employment in con- 

 nection with steam-boilers. A report of great value may be anticipated. 

 Editor. 



USE OF ZINC FOR THE SHEATHING OF VESSELS. 



The Yieille Montagne Company of Belgium are now engaged in manufac- 

 turing extensively zinc for the sheathing of vessels. In a pamphlet issued 

 they present testimonials of the use of zinc sheathing in various ships for eight, 

 nine, and even twelve years. The average duration of a zinc suit is, however, 

 fixed at six years. The superiority of the zinc to copper in point of durability 

 is based on the following grounds : 



1. It is used in thicker sheets than either copper or yellow metal. 



2. It does not oxydize or corrode, as copper or brass, by immersion hi sea- 

 water ; on the contrary, it is covered with an adhesive coat of peroxyd, which 

 becomes a permanent protection to the body of the metal. 



3. When barnacles or sea-weeds that may have gathered upon it, fall, or 

 are scraped off, the metal remains almost uninjured, while, with a copper or 

 brass sheathing, they commonly leave it greatly thinned, eaten through, and 

 crumbling off. 



The cost of copper in sheets, in relation to that of zinc, is generally as 3 ^ is 

 to 1 ; if to this be added the well-known fact that a suit of copper sheathing 

 seldom lasts more than four years, the economy of using zinc will be self- 

 evident. The same conclusion applies to brass or yellow metal sheathing, the 

 cost of which is only one sixth less than that of copper, and which is acknowl- 

 edged seldom to last more than three years. 



An attempt has also been made with success, to construct a vessel entirely 

 of zinc. A schooner built of zinc constructed at Nantes, France, in 1854, 

 has since been employed as a regular trader between Marseilles and Rio 

 Janeiro. The zinc plates used overlapped each other one inch, and were 

 riveted with wrought zinc rivets, one and a quarter inches apart. 



A zinc vessel, while it is hardly inferior in strength to one of iron, has over 

 the latter many advantages : 



1. It will cause no deviation of the compass. 2. The plates not being liable 

 to corrode or rust, do not require painting. 3. In ordinary cases of collision, 

 while iron would in all probability crack or break, causing a leakage in the 

 .vessel, zinc would yield and bend without endangering the safety of the vessel 

 and hands, or interrupting her course. 4. In the event of stranding near 

 shore, and in a position and under circumstances allowing salvage, the zinc 

 hull might be cut or sawed in pieces, having a real value, while the iron hull 

 would be abandoned as worthless. 



NEW METALLIC ALLOYS. 



Messrs, de Ruolz and Fontenay, of Paris, have invented an "alloy which 

 may be employed for almost all purposes to which silver is usually employed. 



