42 



REMARKS ON THE PRESERVATION OF TIMBER. 



Vitriol, 2. Spirit of minder., 2. Tar- 

 tar solub., 2. Sal. diuret., 2. Sal. am- 

 moniac, 3. Saline mixture, 3. Nitre 4. 

 Salt of hartshorn, 4. Salt of wormwood, 

 4. Borax, 12. Salt of amber, 20. Al- 

 um, 30. 



Besides these there are various substan- 

 ces which possess in a high degree, ajiti- 

 ceptic properties, among them camphor 

 ranks very high, 



Aqua Regia, A combination of nitric 

 and muriatic acids. 



In the new nomenclature, it is called 

 nitro-muriatic acid; it is called aqua regia, 

 as the only acid formerly known to dis- 

 solve gold. 



Aqua Secunda, Aqua-fortis diluted 

 with water, and employed in the arts. 



Atom, In Philosophy, a particle of 

 matter so minute as to admit of no division. 



REMARKS ON THE PRESERVATION OP 

 TIMBER. 



The following methods are reccomend- 

 ed for the purpose: 



1st. To girdle the tree by cutting away 

 a ring of the alburnum, in the early part of 

 summer, thus putting a stop to the further 

 ascent of the sap, and then to sufTer' it to 

 stand until the leaves should have expend- 

 ed, by their growth or transpiration, all 

 the fluid which could be extracted by them 

 previously to the death of the tree. The 

 wood would thus, probably be found in 

 the driest state, to which any treatment 

 could reduce it in the living state. 



2nd, Strip the tree of its bark in the 

 spring, and fell it in ^the succeeding au- 

 tumn. 



3d, Consists in immersing the green 

 limber in clear water for about two weeks, 

 after which it is taken out and seasoned 

 in the usual manner. A great part of the 

 sap, together with the soluble and ferment- 

 able matter, is said to be dissolved or re- 

 moved by this process. Running water 

 is more effectual, than that which is stag- 

 nant. It is necessary that the timber 

 should be sunk, so as to be completely un- 

 der the water, since nothing is more de- 

 structive to wood than partial immersion. 

 4th, The sap to be extracted by an air 

 pump. 



5th, The but-end of the trees to be placed 

 in water, with the branches and leaves on 



them, the water will displace the sap; 

 seasoning afterwards removes the water. 



Gth, Pyro-ligneous acid, tar, bitumen, 

 and other resinous substances; or lime in 

 powder, or mixed with water, or other 

 fluid; common salt, (muriate of soda,) de- 

 prived of its bitter deliquescent salts, 

 (which substance is said to cause damp- 

 ness in sea vessels;) nitre, alum, and some 

 of the metallic salts, such as sulphates of 

 iron, copper, and zinc. Wood, boiled in 

 a solution of the former of these metals, 

 and afterwards kept some days in a warm 

 place to dry, is said to be impervious to 

 moisture. Oxide of iron combined with 

 an antiseptic fluid, and forced into the 

 spongioles of the wood; or a fluid of this 

 character, maybe combined with any an- 

 tiseptic finely pulverized solid substance, 

 and forced in the same manner by hy- 

 darulic or other pressure, into the spongi- 

 oles of the wood. Corrosive sublimate 

 is also recommended. 



(See article page 6, on this subject.) 



ON A METHOD OF DRAWING EXTREMELY 



FINE WIRES. 



By W. H. Wollaston, M. O. F. R. S. 



Artists who use silver wire in large 

 quantities, sometimes begin with a rod 3 

 inches in diameter, and ultimately obtain 

 wires of no more than -^\-^ of an inch in 

 thickness. If in any stage of this pro- 

 cess a hole be drilled longitudinally 

 through the silver rod, having its diame- 

 ter one-tenth of that of the rod, and if a 

 wire of pure gold be inserted so as to fill 

 the hole, it is evident that by continuing 

 to draw the rod, the gold within it will be 

 reduced in diameter, exactly in the same 

 proportion as the silver; so that if both be 

 thus drawn out together till the diameter 

 of the silver is -^\-^ of an inch, then that 

 of the gold will be only -j-^'po, and of such 

 a wire, five hundred and fifty feet will 

 weigh no more than one grain. Now, if 

 such silvered gold wire be steeped for a 

 few minutes in warm nitrous acid, the sil- 

 ver alone will be dissolved, and the gold 

 will be left untouched. In this way 

 the author succeeded in making gold 

 wire of very great tenuity, but he expe- 

 rienced great difficulty in drilling the hole 

 in the silver rod and inserting the gold. 

 He therefore made the experiment of sub- 

 stituting platina for gold wire, as its infu- 



