426 



Wright and Kreider — Relation between 



have announced that under these circumstances an invariable 

 excess of laevo crystals should form. Three more crops were 

 grown under the same conditions and curiously again these 

 three all had an excess of laevo crystals. Other crops were 

 then grown and the percentage of dextrose in solution increased, 

 but it was found to have no effect, the crystals coming down 

 one time with an excess of dextro and the next time with an 

 excess of laevo, as is shown by Table IV, results which in no 

 way differ from those obtained where the crystals are formed 

 in the ordinary way. 









Table IV. 













% of Dextro. 



Remarks. 



1. Resultant rotation 





... = + 2-84 



65-8 ) 



First set. Good crop 

 of sharp and clear 

 but small crystals. 

 From mother liquor 

 of 1-3. 



2. " 



II 





+ 2-46 



63-7 [■ 



3. " 



u 





+ 0-94 



55-2 \ 



4. 



u 





— 0-37 



47-9 ) 



5. 



w 





— 0-7 



46-1 [ 

 43-1 \ 



6. " 





— 1-24 



Good clear crystals. 





Crystals by 



Excess by 



j 





No. 



Wt. 



No. Wt. 







h j Dextro.. 

 ' ( Laevo .. 



9? 



0-670 



__ 





Clusters and frag- 



16? 



0825 



7? 0-255 



44-8 



ments made number 













uncertain. 



g { Dextro.. 

 ' } Laevo _ _ 



3 



1-060 



0-455 





4 large crystals, of 



13? 



0-505 



10 



67-7 



which 3 were dextro 













and 1 laevo; remain- 













der small and all 













laevo. 



9. Resultant 



rotation 





= — 055 



46-9 



From mother liquor 

 of 7-8. 









, Q j Dextro.. 



32 



1-640 



18 0-875 





Mother liquor of No. 



( Laevo ._ 



14 



0-765 





68-2 



9 with addition of 

 some of original so- 

 lution. Large, fine 



crystals. 



,, j Dextro. . 

 Ll '{ Laevo .. 



104 



1-172 



15 0-147 







89 



1025 







53-3 



Uncertain, 0*031 gm. 



Pope and Kipping do not state the number of results upon 

 which they have based their conclusions, but our experience 

 indicates that, whatever be the undetermined cause* of this 

 varying excess of dextro or laevo crystals, whenever several 

 crops are allowed to grow under the same circumstances, each 

 being portions of the same solutions, taken at the same time, 

 the causes acting on each are likely to be the same, and to give 

 rise to an excess of the same kind of crystals in each case. 

 Therefore to determine whether or not any special influence is 

 exerted by extraneous forces a sufficient variety should be 

 given to the experimental conditions to assure the unmistaka- 

 ble revelation of this influence. 



* Is it the influence of the first crystal formed? 



