170 ANNUAL OF SCIENTIFIC DISCOVERY. 



ON THE FUSION AND VOLATILIZATION OF BODIES. 



FOR some time past, M. Despretz, of Paris, has been actively en- 

 gaged in a series of experiments, with a view of determining the 

 effect of the application of an intense heat upon the nature of different 

 substances. For this purpose, he has sought to combine the three 

 most powerful sources of heat, the sun, the electric current, and com- 

 bustion, and to apply them united at one point. To effect this, he 

 employed a galvanic battery equal to 185 pairs, an annular lens nearly 

 90 centimetres (about a yard) in diameter, and a blowpipe of carbn- 

 retted hydrogen. By the addition of another source of heat the power 

 of the battery was found to be so greatly increased, that hard and 

 compact magnesia, which, under the action of the battery alone be- 

 came pasty, immediately volatilized in the form of white vapor by 

 the concurrent action of the battery and lens. Pure anthracite coal, 

 subjected to the simultaneous action of the battery, lens, and blow- 

 pipe, appeared to fuse and fall in drops. Charcoal was also caused to 

 fuse and volatilize. By the application of the electric fire alone, 

 tungsten, boron, silicium, and titanium were readily fused, and the 

 three latter volatilized. The tungsten, when fused, became so hard as 

 to be polished only with diamond dust. This great hardness suggests 

 its application for various useful purposes in the arts, as the cutting of 

 precious stones, &c. By this same battery 80 grammes of palladium 

 were instantly reduced to a beautiful button, and 250 grammes of pla- 

 tinum were reduced to a liquid in a few minutes. In fine, says M. 

 Despretz, there is not a single metal which can resist the electric fire. 



With a battery of 600 elements alone, charcoal has been so intense- 

 ly heated, that an acicular rod has been seen to bend under the form 

 of an arc of a circle, or even under the form of an S. The charcoal 

 in this condition is almost always fused and partially converted into 

 graphite. When two charcoal rods thus heated were pressed against 

 one another, the positive rod penetrated into the negative charcoal to 

 the depth of four or five millimetres. When the volatilization, which 

 is effected by this battery, takes place, it is manifested under the form 

 of a black cloud, which rises from the entire surface of the charcoal, 

 and is deposited in great part upon the sides of the vessel in which the 

 charcoal which unites the two poles of the battery is placed. In most 

 of these cases the experiments were made in nitrogen, or some gas 

 not supporting combustion, at a higher pressure than that of the 

 atmosphere. The apparatus by which these conditions are fulfilled 

 is of cast-iron, fitted with a movable cover, and thick glass plates, to 

 afford a view of the interior. It contains, also, various arrangements 

 inside, for supporting and connecting the various substances to be op- 

 erated on. When it is desired to operate in vacuo, a large bell-glass 

 receiver on the platinum of a pneumatic apparatus is substituted. A 

 circular iron plate and a metallic grating defend the platinum and the 

 glass against the projection of powerfully heated globules and sparks. 

 In experiments in the open air, a box is used, open on the side of the 

 battery, and closed on the side of the observer. An opening exists, 

 fitted with blue glass. By these arrangements the danger of these 



