Sessional_Paper_1907 — Page 887

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7. Much of the milk used here is obtained from the Buffalo. Samples on being boiled have occasionally given a deposit, which has been found to be casein. This same sub- stance has been noticed in some brands of condensed milks after such have been exposed to air. Slight acidity in the milk is the cause of the formation of this deposit.

8. Chinese Rice or Birth Cakes have been the subject of enquiry. They are composed of rice and sugar. The rice has been rendered more digestible by dry heating the washed grains, then powdering. These cakes mixed with cold water are given to new-born infants during the first week, as Chinese women do not usually have enough milk for feeding purposes for the first few days.

BUILDING MATERIALS.

9. In response to an enquiry as to the tensile strength of mortar made from red earth and shell lime, as compared with that made from sand and the same line, an investigation has been conducted by Mr. T. L. PERKINS and Mr. EDWARDS of the Public Works Depart- ment, and myself. Ordinary good shell (mostly coral) was converted into slaked lime, 100 parts of which gave the following figures on analysis :-

Insoluble matter-grit,

Soluble silica,

Magnesia,.

Sulphuric anhydride,

Slaked lime,

Total,

.S

.7

.1

trace.

98.4

.100.0

The lime thus prepared in the laboratory was quite free from carbonate.

Red earth has the following composition in 100 parts as determined from an analysis performed in 1903 :-

Insoluble matter-quartz,..........

Soluble silica,...

Alumina,

Ferric oxide,

Water,

Magnesia,

Total,....

51.0

12.8

20.8

4.4

10.0

trace.

99.0

From its composition, red earth should give a mortar setting under water, and from an examination of the table, it will be seen that it behaved as expected.

The sand was the To Kwa Wan variety and had been carefully sifted down to a practically uniform size.

The briquettes were, except in experiment No. 5, of one square inch section, and in the first nine experiments the ingredients were mixed with great care. In experiment No. 5 smaller briquettes were used and the results calculated to one inch section.