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Tests of Golden Bay Cement. The following are selected test results showing the tensile and compressive strength of Ihe finished article, by Sydney F. Strudwicke, works chemist, obtained at the works laboratory :

COMPRESSIVE STRENGTH TESTS OF GOLDEN BAY CEMENT BY NEW SOUTH WALES PUBLIC WORKS DEPARTMENT. Sand is that used as standard l>v Public Works Department, New South Wales, obtained from Nepean River, and sifted through a sieve of 400 meshes and retained on a sieve of 900 meshes per square inch.

General. The Golden Bay Cement Company (Limited) has a nominal capital of £60,000 in 60,000 shares of £1 each, of which 2,400 fully paid up were issued, and 57,600 contributing shares now fully called up, in addition to which the company has issued £25,000 in debentures. The estimated value of the quarries in the balance-sheet is £5,791, and of the works £78.938. During the year ended 30th June, 1916, £5,744 was distributed in dividends. The output stage was arrived at during September, 1911. The output of Portland cement for 1916 was about 22,000 tons: the maximum capacity of the plant is about 30,000 tons. The manufactory is worked full time i.e., three shifts per day for seven djiys per week. The quarries tire worked one shift per day during six days per week. Ninety men on the average are employed at the quarries and works. The managing engineer at the works is Mr. J. A. J. McLaren (first-class certificate under the Mining Act), and the works chemist Mr. Sydney F. Strudwicke, to both of whom I am greatly indebted for much of the informal ion contained in this report. VII. STATE All) TO MINING. (1.) Subsidizell Prospecting. During the year ended 31st March, 1918, nine approved prospecting parties were granted subsidies amounting to £1,933 55., of which £882 Bs. Bd. was expended during that period. In addition to this, £518 Bs. Bd. granted during previous years was expended by fifteen parties during the past financial year. The following statement shows the total expenditure during the year ended 31st March, 191.8: — £ s. d. Tauranga County .. .. .. .. .. .. 125 0 0 Thames County .. .. .. .. .. .. 60 0 0 Ohinemuri County .. .. .. .. .. .. 25 0 0 Pelorus Road District .. .. .. .. .. 15 0 o Wairau Road District .. .. .. . . .. .. 37 10 0 Inangahua County .. .. .. .. .. .. 53 11 8 Buller County . . .. .. .. .. . . 70 0 0 Westland County . . .. .. .. . . . . 686 8 6 Prospecting associations, &c. . . .. .. .. . . 328 7 2 Total .. .. .. .. .. .. £1,400 17 4

I _ . . Nature of Tests according to British ii 1 ; ..i'wo'.i- r Standard Specification. | , S( ,, pt ,. mbo ,, ,<„.,. Packed in June, 1915. Supplied to Public Works, Wellington ! Packed and Blenheim, September, 1910. 28th September.l 915. I i Fineness Residue on 180 sieve .. l(i-0 per cent. Residue on 70 sieve .. .. 0-8 ,, Sotti no-time — Initial set, .. . . .. 1 hours Final set .. .. .. 1\ „ Soundness Boiling-water tests .. .. All perfect Expansion by I'' chatelier .. 2 millimetres Specific gravity .. .. 3-105 Tensile strength neat cemenl |,h. persq. in. A tier I day .. .. 333 7 davs . . . . 640 „ 28 days .. .. 656 3 months .. .. 732 ,, 6 months . . ' . . Not made ,, I year L4-0 per cent. 0-6 I hours 6 „ All perfect 2 millimetres 3-137 Lb. per sq. in. 301 733 S( 13 SI2 840 Not made 12-d per cent. 12-0 per cent. (I-1 „ D-1 2.1 hours 3 hours. 5 „ 5 „ All perfect All perfect I.', millimetres 1-1 millimetres. 3-106 3-121 Lb. per «<|. in Lb. per s<|. in. 405 381 777 857 SOI i 751 814 71)7 839 Not made. 845

Naluro of Tests. Standard required. Results N.S.H'.l'ulilie Works Department. Compressive, strength (cubes 50 sq. cm. : face about 2-75 in, : cement I part, Standard sand 3 parts) LI,, per sip in. After 1 day in air and 27 days in cold wafer . . . . 2.250 After 1 day in air, (i days in cold water, and a further 21 3.570 days in air Lb. per sip in. 4,170 4,840