UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 451 
Contribution from the Bureau of Animal Industry 
A. D. MELVIN, Chief 
Washington, D. C. 
PROFESSIONAL PAPER 
December 14, 1916 
THE CHEMICAL COMPOSITION OF LIME-SULPHUR 
ANIMAL DIPS. 
By Robekt M. Chapin, Senior Biochemist, Biochemic Division. 
CONTENTS. 
Page. 
Experimental materials and methods 1 
Effect of storage 2 
Effect of lime added after dilution 3 
Effect of varying lime-sulphur ratio 4 
Effect of varying period of boiling 5 
Effect of varying concentration 6 
Occurrence and relations of calcium sulphite . 7 
Page. 
Ratio of polysulphid to thiosulphate 8 
Lower polysulphids ; effect of excess of lime ... 9 
Higher polysulphids ; effect of oxidation 11 
Conclusions 12 
Practical applications 15 
References to literature 16 
The literature on the subject of lime-sulphur solutions is already 
voluminous. But even the ablest investigators have been handicapped 
by limitations in their methods of analysis, while some of the pub- 
lished work, especially in recent years, has been of such a character 
as to bring the whole matter into a state of confusion. Inasmuch as 
the writer has been able to develop some new methods of analysis 1,2a 
which appear in several ways superior to former ones, it has been a 
logical step to utilize these new methods in a general study of the 
composition of lime-sulphur solutions. The information so obtained 
appears to determine decisively some facts which previously could 
be only a matter of conjecture or at least only qualitatively studied, 
and others which have been the subject of dispute, although it very 
likely brings out little radically new. Lime-sulphur solutions are 
of considerable practical importance and precise information re- 
garding them is of distinct value. 
EXPERIMENTAL MATERIALS AND METHODS. 
The general plan of investigation was necessarily simple, merely 
involving the preparation of solutions according to different formulas 
and under different conditions, with subsequent analyses and com- 
a The figures refer to the list of references at end of bulletin. 
59847° — 16 
