Hours. Mean result of Readings.
Lbs.
Mean Strength of the Paper.
Lbs.
8a 14·112·1
b 10·1
10a 15·413·2
b 10·9
19a 16·514·0
b 11·4
21a 15·214·0
b 12·8
33a 13·412·4
b 11·4
35a 14·513·6
b 12·7

Tests for Strength on Papers, Sized only.

Hours. Mean result of Readings.
Lbs.
Mean Strength of the Paper.
Lbs.
8a 22·720·0
b 17·3
10a 28·523·2
b 18·0
19a 22·521·0
b 19·5
21a 26·021·7
b 17·5
33a 15·015·0
b 15·0
35a 14·215·3
b 16·5

Tests for Strength on Paper Sized and Glazed.

Hours. Mean result of Readings.
Lbs.
Mean Strength of the Paper.
Lbs.
8a 25·823·6
b 21·4
10a 28·423·6
b 18·9
19a 27·022·9
b 18·9
21a 24·922·7
b 20·6
33a 16·115·2
b 14·4
35a 17·516·2
b 15·0

It may also be noticed that the strength of the finished paper after twenty hours' beating, as in class B, is equal to that of the paper after nine hours' beating, as in class A. This is curious, especially in view of the fact that the percentage of gelatine in the papers of class B. is only 4·4 per cent. as against 6·0 per cent. in class A.

The relation of the percentage of gelatine to the period of beating thus becomes a matter of interest, and well worth investigation. The figures are suggestive of further experimental research along definite lines.