FOOTNOTES:

[1] While the addition of animal fat like margarine raises the melting point, rape-seed oil and other vegetable oils lower it.

[2] The fat to be analysed is saponified with soda or potash, and then the fatty acid set free by hydrochloric acid. If water be now added, 11 or 12 per cent. of the fatty acid will be dissolved, if the fat is butter; less than this if it is a mixture; and not more than 5 per cent. if no butter is present in the fat.

[3] Freshly made; of which 1 c.c. = ·00001 grm. of N₂O₃

[4] Made by dissolving ·395 grm. of KMnO₄ in 1,000 c.c. of water. Each c.c. of this solution =·0001 grm. of oxygen available for oxidation.

[5] Caused by the liberation of iodine. Thus—

K₂Mn₂O₈ + 8 H₂SO₄ + 10 KI = 6 K₂SO₄ + 2 MnSO₄ + 8 H₂O + 5 I₂.

[6] Of the strength of 1 grm. of crystalline sodium thiosulphate to 1 litre of water.

[7] In practice one has frequently to be contented if the CO₂ does not exceed 1 part per 1000 of air; and if the room is clean and free from dust, this higher limit may be accepted.