412 Foreign and Miscellaneous Intelligence. 



density lies, and in what degree the volume of the solid metal exceeds 

 that of the fused, has, as far as we know, not yet been ascertained ; 

 but the former is probably very near the point of congelation ; and of 

 the latter, an approximate evaluation may, according to Professor 

 Marx, be made in the following manner. If a quantity of bismuth 

 be fused in an iron spoon or a glass tube, and then removed from the 

 fire, the mass remains fluid for some time ; it then congeals at the sur- 

 face, but after the whole seems to be quite solid, all at once a large 

 quantity of globular masses protrude from the surface, which are 

 always proportional to the quantity of the metal employed, and 

 may perhaps serve to determine the quantity of expansion ; this was, 

 according to several experiments of Professor Marx, found to be 

 about -^ of the weight of the whole, and consequently less than a 

 third of the expansion of water. The force with which bismuth 

 expands is so considerable, as to break glass tubes in which the fused 

 metal is allowed to cool : thus, if a thermometer tube is plunged into 

 fused bismuth, and then filled with it by sucking the metal up, it 

 always breaks within a short time with a loud cracking, and in several 

 directions, but mostly longitudinally, so as to form long parallel glass 

 fibres. For the success of this experiment, it is, however, necessary 

 to make the column of metal long enough, otherwise its longitudinal 

 increase will cancel the expansion. The following were the alloys 

 of bismuth, which Professor Marx examined : 



i. Bismuth and Sodium. Four parts in volume of powdered 

 bismuth, and one of sodium, were heated in an iron spoon. Long 

 before the fusion of the bismuth, the sodium united with it, with 

 the evolution of vivid light ; the alloy was more fusible than bismuth, 

 of a steel grey colour, and did not change by the contact of the 

 air, until after some days, when its surface became covered with 

 a black powder. If the alloy be fused, and then allowed to cool, the 

 projections also formed, but to a much less degree than in pure 

 bismuth ; nor were the thermometer tubes burst, as in the above expe- 

 riment. The alloy, with potassium, offered nearly the same results. 



ii. Bismuth and Arsenic. This alloy, consisting of three parts of 

 the former, and one of the latter, did not seem to expand at all 

 when becoming solid ; on increasing the quantity of bismuth, the 

 effects ofjexpansion gradually became visible, and in the alloy B M Ar l 

 were almost as great as in bismuth alone. 



iii. Bismuth and Antimony. It having been frequently remarked 

 that antimony, like bismuth and water, expands on becoming solid, 

 Professor Marx made several experiments in order to ascertain it, 

 but without coming to any decided result ; the alloy of both metals, 

 in equal parts, exhibited the same phenomena as pure bismuth. This 

 was also the case in the alloys B 1 Ant. 2 , and B l and Ant. 4 , though in 

 a less degree. 



iv. Bismuth and Zinc. Zinc on becoming solid contracts so 

 much, as to exhibit the contrary to what is observed in bismuth, the 

 surface becomes depressed, and the wire in the thermometer tube 

 often breaks into several pieces ; the tube also bursts sometimes, but 





