[71]

Albury Aug. 5 – 1871

Using common pin I removed from two different minim glasses 5

(These are Pins used)

minims by taking drops on head of pin, & drying it by touching blotting–paper & then removing whole drop. – No doubt the glands of Drosera wd not remove so completely - I thus found that 300 of my drops = 5 minims. ∴ 1 minim = 60 drops. Of course this not absolutely accurate, but very near. I find by mark on blotting paper, pin being immersed vertically, that drops very equal – an average result from 5 or 6 wd be almost exactly equal.

See over for Table,—

[71v]

60 Pin Head drop = 1 minim

Pin-Head drops Minims

300 = 5.

12/3600 = 12/60 = 1 drachm

8/28,800 = 8/480 = 1 oz

Hence in solution of 1 gr to 1 oz one of my drops would contain 1/28,800 of substance.

If 1 drop acted on 3 Heads

28,800 [x] 3 [=] 86,400

what proportion by weight on nitrogen in 100 part of dry carbon of ammon

carbon of ammon