134 ANNUAL OF SCIENTIFIC DISCOVERY. 



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burns no more readily than well-clried fresh hay, although its 

 ai)poarance would seem to indicate great combustibility. AVe 

 should have less tear of its ignition than of pine wood similarly 

 carbonized. — Scientific American. 



The Ili/draidic Scraping of the Torquay Water Main. — Mr. R. 

 E. Froude, at the meeting of the British Assoeiati(m, read a paper 

 on the operations which were rendered necessary l)y the continu- 

 ally decreasing supply of water, which resulted in raising the 

 supply from 320 gallons, in 18C4, to 564 gallons per minute in 

 18G7,'to 034 gallons in 1808, and to GOO gallons in 18G9. The 

 plan adoi)ted was that of passing through the main a piston, armed 

 with a serajjcr. 



Average Dutij of Cornish Engines. — An estimate of the average 

 duty of this class of engines, based on observations made upon 18 

 engines during one month, shows the following results: They 

 have consumed 1,))77 tons of coal, and lifted 10.2 million tons of 

 water 10 fathoms high. The average duty of the whole is, there- 

 fore, 50,100,000 lbs., lifted one foot high, by the consumption of 

 112 lbs. of coal. 



Ahnniniuni Bells. — It appears that some Belgian manufacturer 

 has just had a bell cast of aluminium, and with good results. It 

 is of course extremely light, so that, though large, it can be 

 easily tolled; its tone is reported to be loud and of excellent 

 pitch. Aluminium is the most sonorous of all metals. — Engi- 

 neer. 



A new Alloy y forming a beautiful white metal, very hard and 

 capable of taking a brilliant polish, is obtained by melting to- 

 gether about 70 parts of co})per, 20 of nickel, bh. of zinc, and 4i 

 of cadmium. It is, therefore, a kind of German silver, in which 

 part of the zinc is replaced by cadmium. This alloy has been re- 

 cently made in Paris for the manufacture of spoons and forks, 

 which resemble articles of silver. 



lloto Oroide is Made. — Oroide, the beautiful alloy resembling 

 gold, is a French disco ver}-, and consists of pure copper, 100 

 parts; zinc or (preferably) tin, 17 parts; magnesia, 6 parts; sal- 

 ammoniac one half part; quicklime, one-eighth part; tartar of 

 commerce, 9 parts. The copper is first melted, then the mag- 

 nesia, sal-ammoniac, lime, and tartar in powder are added little 

 by little, briskly stirring for about half an hour, so as to mix tho- 

 roughly ; after which zinc is thrown on the surface in small 

 grains, stirring it until entirely fused. The crucible is then cov- 

 ered, and the fusion maintained about 35 minutes, when the dross 

 is skimmed off, and the alloy is ready for use. It can be cast, 

 rolled, drawn, stamped, chased, beaten into a powder or leaves; 

 and none but exeelhsnt judges can distinguish it from gold. 



S. T. Clements, D.D.S., writes to the " Dental Cosmos" that 

 although wax and resin, shellac, varnish, and li(]uid silex are 

 recommended for mending jilaster models, neither, in his expe- 

 rience, can compare with sandarac varnish. Saturate the broken 

 surfaces thoroughly, and press them well together. Allow it to 

 diy, and the model will stand all the manipulation required. 



Safety Envelopes. — It is stated that the thick, tough sap, found 



