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2 BULLETIN 1389, U. S. DEPARTMENT OF AGRICULTURE  — 
by its use, other precautions may be omitted, with very serious 
injury to health as the result. 3 
The investigation here reported was undertaken for the purpose 
of determining the rate of deterioration of chlorinated lime, as 
expressed by its loss of available chlorine, when stored under different 
conditions of temperature and packing. 
RESULTS OF PREVIOUS INVESTIGATIONS % 
Thiimmel (1/2) determined the available chlorine content of 
chlorinated lime bought from local druggists when received and after 
it had been stored for two months (July and August) in open vessels — 
in a place protected from light... He found that the loss in available 
chlorine ranged from 0.6 to 6.6 per cent. The loss in the: upper 
layers of the samples was slightly greater than that in the lower 
portions. Table 1 shows the results of another determination of 
the loss of available chlorine in samples of chlorinated lime when 
packed in glass containers and stored under varying conditions 
conducted by Thiimmel. 
TABLE 1.—Available chlorine in chlorinated lime lost under varying stoiage con- 
ditions (Thtimmel) 
Available 
chlorine | Loss 
Storage conditions 
x Per cent | Per cent 
ATstrme ofpaekinigs (es __ eT SOO es ee ee eee ee eee) Fase. See 3539 22. ae 
Protected from the light for 2 months: 
Openrin*eelar® 2-72. 0ee CS SEE Ae. Se EE EA I ES ek 
Pattinson (7) made deterioration tests on chlorinated lime in three 
casks, each holding 6 hundredweight of the material. Twelve sub- 
samples from each cask were stored for 11 months in bottles in a 
cellar where the temperature ranged from 38° to 62° F. This in- 
vestigator concluded that chlorinated hme kept for about 12 months, 
in either flasks or bottles, at temperatures halve 60° F. loses not 
more than 2 to 3 per cent of available chlorine and less than 1 per 
cent of total chlorme. Later Pattinson (S) made tests in which the 
subsamples were kept for 11 months at 60°, 70°, and 80° F. At the 
end of the 11 months chlorinated lime originally containing 36.1 per — 
cent of available chlorine contained 30.1 per cent when kept at 60°, 
28.3 per cent when kept at 70°, and 19.1 per cent when kept at 80°. 
During this period there was also a regular and corresponding in- 
crease of chlorine existing as chloride. In the samples which were 
kept at 60° F. the chlorate content decreased to zero; in the other 
samples it decreased to zero at first and then rose, the samples kept 
at 80° F. showing the largest increase. ; 
Boyer and Durand (/) found that dry chlorinated lime undergoes 
a change about twice as quickly in the open air as when exposed in a 
closed room, and somewhat more rapidly in hght than in darkness. 
This change takes place much more promptly in an atmosphere con- 
taining hydrogen sulphide, carbon dioxide, or hydrochloric acid 
vapors than in ordinary air. f 
mith (11) stored subsamples of four lots of bleaching powder — 
under similar conditions for one year and analyzed newly-opened — 
