418 Wright and Kr eider — Relation between 



wooden box, which was made long enough to permit of their 

 being placed at sufficient distance from each other to avoid any 

 appreciable interference in their magnetic fields. To counter- 

 act any possible slight difference in the effect of the two coils, 

 the tubes, after half of the time of heating, were changed from 

 one coil to the other and the magnetic conditions with them. 

 Finally, to avoid any variation in the action due to a difference 

 of density in the two tubes, since the amount of water em- 

 ployed was insufficient for a complete solution of the acid at 

 the ordinary temperature, the tubes were agitated at certain 

 intervals to insure uniform and equal density in each. 



With these precautions to have the conditions of each tube 

 identical save in the magnetism, the series of determinations 

 referred to failed to indicate any influence of the magnetic 

 field, the rotation having been diminished by the same amount 

 in each case. 



Experiments upon Racemic acid. 



Experiments were also made, under the same conditions, 

 upon racemic acid ; it being thought that this, being an equi- 

 molecular union of both forms, would be more likely to show 

 an effect when placed in a magnetic field more favorable to 

 the existence of one form than the other. Finally a small per- 

 centage of the dextro acid was added in the hope that a little 

 excess of dextro would help the. turning, but in neither case 

 was any effect noted. 



Experiments on Sodium Chlorate. 



Identical considerations led to a like investigation of the 

 crystallization of sodium chlorate in a magnetic field. 



Landolt and others have found that ordinarily sodium chlor- 

 ate will, if undisturbed during spontaneous evaporation, 

 deposit equal quantities of dextro- and laevo-rotatory crystals. 

 The experiments here recorded also confirm this observation 

 in general. Presumably Landolt has not meant that the quan- 

 tities of dextro and laevo crystals are exactly equal, but that 

 they are practically so, and the number of determinations 

 recorded in this paper, which are only a small part of the num- 

 ber actually made, will show that while there is a tendency to 

 form in equal amounts, there is almost invariably a slight 

 excess of one or the other which often may be considerable, 

 yet to all appearance wholly accidental. 



That there is nothing inherent in the individual mole- 

 cules of this substance which possesses rotary power or which 

 determines the optical activity of the crystalline aggregate, is 



