1918.] The N.Z. Journal of Science and Technology. 
91 
THE MANUFACTURE OF CARBIDE OF CALCIUM IN 
NEW ZEALAND. 
By E. Parry, Public Works Department. 
It is generally assumed that carbide of calcium can be economically manu- 
O */ am " 
factured only on a large scale and in situations where cheaply developed 
water-power is available in conjunction with good harbour and other 
facilities, including coal and limestone of suitable quality at cheap rates. 
This is undoubtedly the case when it is desired to produce carbide for 
export purposes and to supply the principal markets. It does not follow, 
however, that it cannot be profitably manufactured in comparately 
small quantities for local consumption at competitive and profitable 
rates, and it is the purpose of this article to inquire into the conditions 
which affect its manufacture and marketing for home consumption in New 
Zealand. 
At the same time opportunity is seized upon to present in a tabular form 
convenient for reference the reactions and. factors affecting the manufacture. 
Every effort has been made to arrive at reliable figures which are attainable 
in the factory as distinct from the laboratory, given ordinary care ; and, 
whilst the figures presented may not be attainable in all cases for various 
reasons, on the other hand it is possible under favourable conditions and 
with expert attention to improve considerably upon the results given in the 
tables. On the whole, the figures adopted herein represent what might 
be considered probable values with considerable odds in their favour. The 
commercial results given in the tables are, however, subject to considerable 
uncertainty due to fluctuation of values and to local conditions, and in 
some particulars may be subject to considerable modification. An effort 
has been made to disclose the basis of the calculation in each item, so as 
to enable those interested to adjust the figures to suit the circumstances. 
It is, of course, assumed that circumstances are again normal and that 
prices approximate to pre-war prices. 
Numerous inquiries have been addressed to this Department concerning 
the manufacture of calcium carbide, and most of the data here presented 
were originally prepared in answer to such inquiries. They have, however, 
been revised, collated, and rearranged with a view to publication and to 
meet the demand which exists for information on the subject. 
The figures herein used are taken from or based upon information con¬ 
tained in a work by Charles Bingham, who is an undoubted authority in 
regard not only to the technicalities of the subject but also to the manu¬ 
facture and marketing of calcium carbide.* 
Regarding its manufacture for the world market, it is, of course, 
desirable that as many as possible of the factors which enter into the 
manufacture should be present and concentrated in the place of manu¬ 
facture, but in no single instance of which I am aware are all the 
facilities combined. It will be found on inquiry that when power 
and limestone are cheap, coal or coke is dear and the principal market 
* Charles Bingham, The Manufacture of Carbide of Calcium. Raggett and Co., 
London, 1916. 
