1918.] The N.Z. Journal of Science and Technology. 
99 
Table 1. 
Return showing the Total Quantity and Value of Calcium Carbide imported 
into New Zealand during each Calendar Year from 1910 to 1917 inclu¬ 
sive. 
Auckland. 
Wellington. 
Lyttelton. 
Year. 
Quantity. 
Value. 
Rate per 
j Ton. 
Quantity. 
Value. 
Rate per 
Ton. 
Quantity. 
Value. 
|Rate per 
Ton. 
Tons. 
£ 
£ 
Tons. 
£ 
£ 
Tons. 
£ 
£ 
1910 . . 
• • 
• • 
• • 
• • 
. , 
, , 
. , 
, . 
. . 
1911 .. 
1912 .. 
1913 . . 
* * 
* * 
• * 
0 . 
* * 
* * 
1914 .. 
754 
10,249 
13-6 
858 
11,692 
13-6 
427 
6,131 
14-35 
1915 .. 
766 
10,454 
13-65 
750 
9,938 
13-25 
350 
5,039 
14-4 
1916 .. 
701 
9,122 
13-0 
666 
9,222 
13-8 
480 
6,010 
12-5 
1917 .. 
296 
5,273 
17-8 
255 
5,644 
22 1 
176 
2,815 
16-0 
Dunedin. 
Other Ports. 
Total. 
Year. 
Quantity. 
Value. 
Rate per 
Ton. 
Quantity. 
Value. 
Rate per 
Ton. 
Quantity. 
Value. 
Rate per 
Ton. 
Tons. 
£ 
£ 
Tons. 
£ 
£ 
Tons. 
£ 
£ 
1910 .. 
• « 
. • 
. , 
. . 
, , 
. . 
1,693 
20,708 
12-2 
1911 .. 
, . 
. . 
• o 
. # 
. . 
. . 
2,062 
28,499 
13-8 
1912 .’. 
• • 
# , 
, . 
. , 
. , 
. . 
2,685 
37,668 
14-0 
1913 .. 
• • 
8 • 
. , 
« • 
. , 
. . 
2,316 
32,698 
14-1 
1914 . . 
398 
5,583 
14-0 
519 
8,122 
15-6 
2,956 
41,777 
14-1 
1915 . . 
256 
3,388 
13-2 
497 
7,142 
14-35 
2,619 
35,961 
13-7 
1916 .. 
380 
4,744 
12-45 
523 
6,351 
12-1 
2,750 
35,449 
12-9 
1917 . . 
63 
888 
14-1 
60 
1,446 
24-1 
850 
16,066 
18-9 
Note. —Separate particulars for each port prior to 1914 are not available. The 
imports at the four chief ports only have been recorded separately from 1914 onward. 
Table 2. 
Calcium Carbide.—Reactions and Specification of Carbide and Raw Materials. 
Reactions, calcium carbide :— 
CaO + 3C = CaC 2 + CO. 
56 + 36 = 64 + 28. 
0-875 + 0-564 == 1-0 + 0-439. 
Reactions, lime :— 
CaC0 3 = CaO + C0 2 . 
100 ^ = 56 + 44. 
1-785 = 1-0 + 0-785. 
Quality of coke : Ash should not exceed 7 per cent .; phosphoric acid, 0-04 per cent ; 
sulphur, 1-5 per cent.; iron, 0-6 per cent. 
Quality of limestone : Phosphoric acid should not exceed 0-01 per cent, if coke already 
contains 0-04 per cent. ; silica, 1-25 per cent. ; sulphur, not more than a trace if 
the coke is high in sulphur; magnesia, 0-5 per cent. 
Analysis of typical sample of coke used in the manufacture of carbide : Fixed carbon, 
88-4 per cent. ; ash, 6-68 per cent. ; sulphur, 0-9 per cent. ; phosphorus, trace ; 
moisture, 4 per cent. 
Analysis of typical sample of limestone used in the manufacture of carbide : Calcium 
carbonate, 98 per cent. ; magnesia, 0-5 per cent. ; alumina and iron oxide, 0-5 per 
cent. ; phosphoric acid, 0-01 per cent. ; silica, 0-99 per cent. 
Lime from 98 per cent, limestone contains approximately 56 x 100 -4- 58 = 96-5 per 
cent, oxide of lime. 
Analysis of typical commercial carbide : Calcium carbide, 86 per cent. ; carbon, 1 per 
cent. ; calcium oxide, 10 per cent. ; silicon carbide, 0-6 per cent. ; ferro-silicon, 
1 per cent. ; sulphur compounds, 0-4 per cent. ; magnesia compounds, 1 per cent. 
