Uil 



A list of the literature on bismuth tip till 1909 can be found in 

 a paper by F. 0. Blake ^). Of the more recent experiments must be 

 mentioned those of Kamerlingh Onnes and Beckman "'), who worked 

 at temperatures down to — 258° C. Carbon has been investigated 

 by Roberts, who also ^ives the literature. 



There remains to be mentioned, that researches on crystallized 

 specimens have been made in the Leyden laboratory on bismuth 

 and by Robkrts on graphite. These are very important, as the orien- 

 tation of the principal axis has a o-reat influence on the effect. It is 

 principally from this side that we can expect some light on the 

 othei'wise unnecessarily complicated phenomena. However crystals 

 have been investigated insufficiently. A method to obtain large metal 

 crystals would certainly be of great use. So far reasonably large 

 crystals have only been made with bismuth. 



§ 1. Investigation of antimony. 



We shall use the following notations. 



R' Resistance in the field, 



R// Resistance in the field, when the axis of the crystal is parallel 

 to the field, 



R'± The same with the axis perpendicular to the field, 



R Resistance without a field, wiiile the index at the foot indicates 

 the temperature, at which the measurements have been made, 



Xp field. 



Out of several antimony crystal conglomerates of Merck the best 

 specimens were selected ; the material seemed to be very pure and 

 according to the analysis contained less than Viooo» "/o i^'^n. The 

 pieces were split into thin plates along the basic planes, which were 

 at the same time planes of perfect cleavage. These plates were then 

 immersed in shellac and carefully polished into small rods. At both 

 the ends of one of these rods (long 4 mm, broad 0.55 mm, thick 

 0.15 mm) two copperwires were soldered. These wires, wei-e care- 

 fully insulated with shellac, and the two at one end were bent over 

 the rod so that they came into the same direction as the other two. 

 Then the whole, wires and rods, was slipped into a cylindrical glass 

 tube of 0.8 mm diameter. The wires were then pulled through a 

 brass capillary, in the end of which the tube was fitted. Perpendi- 



1) F. C. Blake, Ann. d. Phys. 28, p. 449, 1909. 



2j 1. C. 



