4 8 7 



condensation, it will be safe to assume that 150 lbs. of sulphur 

 are required to produce 100 lbs. of CS 2 . 



Plant and building; capital cost ... $2,500 



Monthly production 600 lbs. 



* Sulphur, 8 cwt. at $12.50 ... ... $100 



Charcoal, 10 cwt. at $1.50 ... ... 15 



Firewood, etc. ... ... ... ... 50 



Wages ... ... ... ... ... 40 



Interest on capital 10%, sinking fund 15% 52 

 Repairs ... ... ... 40 



$297 



or, roughly speaking, 50 cents per lb. 

 With a consumption of 1,200 lbs. per mensem we have- 

 Establishment charges ... ... $132 



Cost of materials ... ... ... 330 



$462 



or, So. 39 per lb., which is a very great deal lower than carbon 

 bisulphide can possibly be imported for. The cost of materials, 

 of wages, repairs, and capital cost of apparatus have been esti- 

 mated at a very much higher rate than is likely to prevail, an 

 exceedingly low condensation factor has been assumed, and a 

 liberal allowance made for interest and sinking fund. 



I would, nevertheless, suggest that previous to any action 

 being taken, the Government should instruct the Crown Agents 

 to refer the question to either Professor Tilden, F.R.S., Professor 

 of Chemistry, Royal College of Science, or else to Professor 

 T. E. Thorpe, of Somerset House, with the request that they 

 should obtain plans for a plant on the following scale: — 



Daily production required ... ... 70 lbs. 



Working hours per day ... ... 7 



Working days per month ... ... 20 



Temperature of condensing water ... So° F. 



All parts to be easily accessible, readily replaced and as 

 uncomplicated as possible. 



APPENDIX B. 



Other Insect Enemies of Rubber. 



With the exception of Tcrmes gestroi both Para rubber and 

 Rambong are singularly free from insect pests of all descriptions. 



* Present price in London, retail, i6/-per cwt 



