December, ’23] deong: volatility and toxicity of nicotine 
491 
need of such addition but this form of nicotine in the concentrate is 
much more dangerous to handle and is subject to greater losses in 
evaporation. 
Fig. 5—Graph showing volatility rate and comparative toxicity from 
fumigation and spraying. 
Practical Applications. To obtain the maximum efficiency of 
nicotine sulfate solutions, a slight excess of alkali should be added over 
the amount needed to combine with the sulfuric acid present. To one 
pound of nicotine sulfate add three ounces of hydrated lime or freshly- 
slaked burned lime. Then for a two-hundred gallon tank of 1-800 
solution of nicotine sulfate, 6-k* ounces of lime would be required, 
supposing the nicotine solution had a specific gravity of 1.2. If soap is 
used as the spreader, then add three ounces of sodium hydroxide (com¬ 
mercial lye may be substituted) or four ounces of sodium carbonate. 
One of the most convenient forms for the latter is commercial soda ash. 
Waters that are very alkaline might, with the addition of soap or 
calcium caseinate, neutralize the combining acid present. However, 
such waters are not common and, in most instances, the total alkali 
