4 
“On the Water of Thirlmere,” by Harry Grimshaw, 
F.C.S., and Clifford Grimshaw. 
The samples of water of which the following details are 
given were taken by us on August 23rd, 1878, from what 
may be termed the “ upper and lower lakes,” meaning, above 
and below the narrow waist of the lake, where crossed by 
the small bridge. The first taken was the “lower” sample, 
which was obtained on the west side of the lake about 
twenty yards below the bridge. The “ upper” sample was 
taken about three quarters of a mile below the head of the 
lake on the east side. The results of the two samples so 
far as position affects them should therefore be sufficient to 
show any possible divergency which could occur in the 
quality of the water on that account. These two positions 
are shown upon the sketch map accompanying the paper. 
The two samples were analysed separately except as re- 
gards the amounts of ammonia (determined August 28th), 
for which equal parts of each sample were taken, as there 
was not a sufficient quantity for separate analyses. 
The following are the numbers obtained : 
Free ammonia — half a litre of water distilled took T5 cc. 
standard NH 4 C1. 
Albumenoid ammonia — half a litre of water distilled took 
3*0 cc. standard NH 4 C1. 
Total hardness — 70 cc. water took 1 cc. standard soap solu- 
tion. 
Permanent hardness — 70 cc. water boiled 1 hour and made 
up took 1 cc. soap. — (The ammonia analysis common to 
both samples, hardness same in each). 
Solid matter — 100 cc. lower sample gave 0*0045 grams resi- 
due, which blackened on ignition and lost 0‘0025 gram. 
Solid matter — 70 cc. upper sample gave 0*0022 grams resi- 
due, which blackened a little on heating, not so much 
as lower sample, and lost on ignition 0*0007 gram. 
Chlorine — 25 cc. lower sample took (1st) 0*25 cc. (2nd) 0.25 
cc. standard AgN0 3 ; 25 cc. upper sample took (1st) 
0*15 cc. (2nd) 0*15 cc. standard AgNO . 
