of Edinburgh, Session 1869^70. 
Tube A. 
201 
Fluid Used. 
Diameter 
of 
Tube. 
Length 
of 
Tube. 
Tempera- 
ture. 
Pressure. 
Time of Flow 
of 100 Cubic Cents 
in Seconds. 
Water, 
mm. 
•928 
mm. 
914 
17° C 
mm. 
601-97 
69 "2 
Urine, Sp. Gr. 1018 
,, 
,, 
17-5 
,, 
71-3 
Urine, Sp. Gr. 1007 
,, 
,, 
,, 
,, 
70-3 
Cow’s Milk, 
” 
” 
24-6 
594-3 
90'3 
Tube C. 
Fluid Used. 
Diameter 
of 
Tube. 
Length 
of 
Tube. 
Tempera- 
ture. 
Pressure. 
Bate of Flow 
of 100 Cubic Cents 
in Seconds. 
Water, 
mm. 
1-259 
mm. 
914 
15 
mm. 
601-97 
42-1 
Cow’s Milk, 
,, 
,, 
27 
,, 
38-1 
Goat’s Milk, 
” 
22 
” 
36-09 
8. On Cystine (C 3 H 7 N0 2 S). By James Dewar, E.R.S.E., 
Lecturer on Chemistry, Veterinary College, Edinburgh ; 
and Arthur Gamgee, M.D., E.R.S.E., Lecturer on Physio- 
logy, at Surgeon’s Hall, Edinburgh. 
Preliminary Notice. 
With the exception of the physical characters of this rare chemi- 
cal substance, which is only known as an abnormal constituent of 
the human body, we know so very little, that even a few facts with 
regard to its behaviour with reagents may not be altogether unin- 
teresting. 
Cystine has the composition C 3 H 7 N0 2 S ; and crystallises in the 
form of six-sided plates. It forms with hydrochloric, nitric, and 
phosphoric acids, definite crystalline compounds. 
Some of the most important facts with regard to the chemical 
reactions of cystine have been recorded by Dr Bence Jones, who 
for the first time showed that nitrous acid decomposes it with the 
evolution of nitrogen, and that in this operation the sulphur which 
it contained is oxidised to sulphuric acid, whilst a non -crystalline 
