M(1)53
Detection of Petroleum Traces.—In the investigation of cases of suspected arson the question frequently arises as to the presence or otherwise of traces of kerosene in the charred material taken from burnt houses. No very delicate chemical test for petroleum has been published. A piece of apparatus has been devised in this laboratory which depends on the use of oil-soluble dyes which will detect petroleum when present in the proportion of only 2 parts per million, and which is likely to be of considerable use in fire enquiries.
Kwong Tung Shales.—A chemical investigation into the composition of shales in the Sun Ning district has commenced and is still in progress.
STAFF.
12. No change has occurred in the staff during the year.
10th January, 1923.
E. R. DOVEY,
Government Analyst.