596 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



Fusee Watch Chains. 

 Invention has yet found no substitute for these chains, which 

 have great flexibility and strength, and yet are exceedingly slender. 

 Each chain is about eight inches in length, and contains upwards 

 of 500 links of steel, rivited together. The smallest parts can 

 scarcely be distinguished by the naked eye. They are made 

 chiefly by young girls having very small fingers and a delicate 

 touch. The manufacture of these chains has, for the last hundred 

 years, been a staple article of Christ Church, Hants county, England. 



■Preservation of Wood. 



This question, always regarded as one of great importance in 

 Europe, is now commanding more attention in our country, where 

 the great forests are rapidly disappearing. Various kinds of salts 

 and paints have been used for the prevention of eremacausis and 

 dry rot, but all are too expensive, or the methods of preparation 

 too complicated for general application and use. The cheapest, 

 and perhaps the most effective plan is to carbonize the surface of 

 timber. Heat applied externally to wood, so as to char it, renders 

 it inaccessi1)le to fermentation, or forestalls the operation of the 

 active principle of decay. Heat also hardens the layer beneath the 

 charred portion, closes the pores, and prevents those essences, 

 having the anti-septic properties of the creosote, from escaping : 

 thus preparing the material to resist moisture and other influences 

 that lead to decay. 



Until recently, great difficulties have been encountered in apph'- 

 ing the charring process to large combinations of worked-up mate- 

 rials. These have been overcome by M. de Lapparent, the 

 Director of Naval Constructions in France. He proposed to pre- 

 vent the decay of the wooden parts of vessels, caused by the 

 introduction of steam engines, by carbonization, using therefor a 

 jet of flame directed and applied by compressed air. His appa- 

 ratus is extremely simple. Two tubes of India rubber, one lead- 

 ing from a reservoir of ordinary gas, the other from a bellows 

 worked Ijy a treadle, convey into a copper tube simultaneously 

 both the gas and compressed air. As soon as the mixture is 

 inflamed, a temperature suflScient to melt metals is obtained. This 

 is simply an improved Bunsen burner, made portable. Keeping 

 the bellows in action with the foot, all that is required is to direct 

 the mouth of the copper tube with one hand against the surfoco 

 of the wood in position, when it will be charred rapidly and uui- 



