9

C—l 2

The average quantity exported for the twenty years 1895 to 1914 was 8,493 tons, and the average value £499,61.1. The following table gives particulars of the export for the last twelve years: —

Particulars of Kauri-gum exported from New Zealand from 1907 to 31st March, 1918, inclusive.

Dr. Maclaurin's Salt Vacuum Process for cleaning Kauri-gum. Much attention has been given during the year to Dr. Maclaurin's process of cleaning the low-grade gums. After successful laboratory tests a miniature plant with a capacity for treating half a hundredweight at, a time was first constructed, and satisfactory results were obtained. I was then authorized to test the process on a commercial scale, and a plant which would deal with half a ton in a charge was installed at the Government Gum-store in Auckland. The process is known as the "vacuum salt process." The modus operandi is briefly as follows : The gum is introduced into a cone-shaped tank together with a strong solution of common salt. The contents of the tank are agitated by appropriate means and the air pumped out. On stopping the agitation the gum rises to the surface of the salt solution and the dirt sinks to the bottom. The dirt and gum are now easily separated by allowing the lower portion of the solution with the dirt in suspension to run off through a valve at the bottom of the cone into a tank, and afterwards allowing the upper portion of the solution carrying the gum to run off into a second tank. The solution carrying the dirt and that carrying the 1 gum are filtered separately to recover the salt solution, which is used in subsequent operations. The gum is finally well washed in such a way as to remove all trace of salt, and is then dried. The trials made proved very satisfactory, and the results obtained on the large scale were almost equally as good as those obtained in the laboratory. Much of the low grades of gum which come into Auckland from the gurnfields contain anything from 25 to 50 per cent, of dirt and foreign matter. The gum is sifted in the stores, and a certain amount of the dirt removed from it before being exported. The grades known as "black chips" and "dust" are used in large quantities in the manufacture of linoleums. These chips as they are exported contain from. 25 to 35 per cent, of dirt and foreign matter, and the low-grade black dust, from 60 to 75 per cent. Now by Dr. Maclaurin's .process this dirt and foreign matter can be practically all eliminated.

2--C. 12.

Country to which exported. 1£ 107. 108. 109. 1! 110. 1911. 1912. United States of America United Kingdom Germany Canada Australia Belgium France Austria-Hungary Russia Netherlands Sweden Italy Japan.. Hong Kong Argentina Tons. 5,171 £ 381,566 Tons. 2,855 £ 215,291 Tons. 5,127 £ 375,126 Tons. 4,149 £ 263,375 Tons. 3,514 £ 209,216 Tons. 3,894 £ 232,566 2,468 936 53 42 21 9 162,121 27,473 4,512 2,216 821 918 1,799 667 21 155 22 10 1 123,011 23,841 1,646 6,458 1,572 875 104 2,290 639 24 149 17 1 1 140,235 24,111 2,555 8,576 1,770 85 68 3,253 913 66 66 29 19 124 15 6 30 23 151,319 28,016 7,687 4,465 1,899 1,656 3,011 1,976 133 720 779 2,378 1,142 9 75 78 75 131 80 55 35 15 130,767 34,062 1,061 2,559 3,990 5,774 3,968 1,859 1,206 803 417 25 2,468 1 ,053 40 39 123 37 159 2 42 35 15 1 114,640 32,964 3,370 2,487 5,088 3,037 4,611 184 974 952 410 22 1 7 114 147 "l72 2 8 Totals .. 8,708 579,888 5,530l 372,798 8,250 552,698 8,693 465,044 7,587 395,707 7,908 401,305 Country to which exported. II 113. II 114. 1! 116. 1st Ji 31st M inuary to 1st Apr arch, 191fi. 31st Mo il, 1910, to .rch, 1917. 1st Apri 31st Ma il, 1917, to u-ch, 1918. United States of America United Kingdom Germany Canada Australia Belgium France Austria-Hungary Russia Netherlands Sweden Italy Japan.. Hong Kong Argentina Tons. 3,995 £ 308,456 Tons. 4,531 £ 316,200 Tons. 3,312 £ 222,856 Tons. 974 £ 60,010 Tons. 3,158 £ 218,214 Tons. 2,316 £ 164,516 3,390 833 62 80 126 45 112 53 60 15 9 187,547 27,880 4,618 3,933 5,120 3,995 2,617 1,725 2,495 420 300 3,335 373 70 1.9 34 42 14 3 8 20 23 1 148,370 21,193 2,114 1,720 1,519 3,599 329 225 664 560 855 96 1,172 48,585 336 13,548 I ,484 68,378 363 13,982 56 9 4,550 594 "iis 5 8,972 314 133 29 7,7.18 1,982 18 124J271 1,577 5 430 21 2J118 50 3,440| •• 539 "lO "506 8 Totals .. ! | 8,780 549,106 300,271 4,636 304,852 8,473 497,444 4,575 279,133 1,433 82,844 ; 4,862