234 BOTANICAL GAZETTE [OCTOBER 
per liter. No comment is necessary. Again Kahlenberg and 
True (5, p. 116), state, ‘‘as maleic acid at the dilution 1024 is 
dissociated 98.2 per cent. and fumaric acid 78.5 per cent., we 
should expect the latter to be less poisonous than the former if 
the toxic action be due to the H ions alone.” In the table to 
which they refer we find maleic acid 92.8 per cent. at 1024 and 
fumaric acid 78.5 at 20g8. They state further, referring to the 
two acids mentioned, ‘‘we do not place much reliance on the 
results obtained from these two acids as it is questionable 
whether the substances were perfectly pure.” The discrepancy 
above referred to suggests another reason for unreliability of 
results. 
True and Hunkel (22, p. 326), while using gram-molecule 
per liter in their paper, made reference to Kahlenberg and True 
(5, p. 92), where the tables are written gram-equivalent per 
liter. The one kind of table, of course, cannot apply directly 
to the other. 
In regard to the method of preparation of solutions by dis- 
solving a gram-equivalent of the salt, or a gram-molecule of the 
salt, as the case may be, in a liter of water, there is something 
to be said. Those who have made errors in this way are Pfeffer 
(17, p. 146), Detmer and Moor (1, p. 326), Kahlenberg and 
True (5, pp. 85, 87), True (20, pp. 184, 185), True (21, pp. 419, 
411), Heald (4, p. 133), Garry (3, p. 298), True and Hunkel 
(22, p. 326), and Ostwald (14, p. 190). Pfeffer, Detmer and 
Moor, and Garry called them zormal solutions. Kahlenberg and 
True called them gram-molecule solutions and gram-equivalent 
solutions, apparently interchangeably, but meaning generally 
molecular solutions. Ostwald is using Tammann’s table which 
States that the solutions are made by dissolving ~ molecular 
weights, in grams, of the salts in 1000 grams of water.’ 
The objection to the above solutions is not so much to the 
*MacDovaat (10, p. §1) says: “A normal solution of ethyl alcohol is made by 
adding 46 grams of absolute alcohol to a liter of distilled water.” This, to be in any 
sense accurate, should read (after the word alcohol) fo sufficient water to make a liter of 
solution. MacDougal’s statement produces an error of about 58° in 1000%. 
