FRANCIS — ON CASSAVA. 
121 
estimated by a separate experiment and allowed for. The 
usual quantity was taken, and lOOcc. of prussic acid, 
which had been found to contain *02599 gramme of H C N, 
were added. The mixture was distilled. 
Total H C N by distillation . . . *03447 grm, 
H C N natural to juice ... ... *00951 „ 
H C N recovered *02496 „ 
TABLE II. 
Percentage of Water found in Cassava Roots. 
Sweet. 
Bitter. 
' No. of 
Sample. 
i. 
Per cent, of 
H 2 0. 
68-73 
No of 
Sample. 
i. 
Per cent, of 
h 2 o. 
59-40 
ii. 
58-33 
ii. 
60-80 
iii. 
59-13 
iii. 
61*80 
iv. 
61*31 
iv. 
61*24 
V. 
58-25 
v. 
62-07 
vi. 
60-65 
vi. 
67*79 
Mean. . . 
59-40 
Mean... 
61-35 
Although every author consulted by the writer is agreed 
in classifying cassava as either harmless or noxious, several 
discard the notion of the existence of different species, urging 
that the variations exhibited are too insignificant to permit 
of any distinction of the kind. 
Thus, a recent writer, M. Paul Sagot, in an article on the 
manioc or tapioca plant, ( Pkarm . Journ., 3rd series, iii. , 569), 
says : — “ Pohl describes the sweet (non-poisonous) manihoi 
(called aipi in Brazil ; m. a'ipi, Pohl.) as a distinct species 
from the poisonous maniliot (\)uca brava, or mandioca brava, 
of the Spanish and Portuguese Colonies ;) but the author 
agrees with Goudot in thinking that they are only varieties 
of the same species.” 
