Gums, Resins, 



[Jan. 1907/ 



C.I.F. Terms (Delivered Weights.) 

 20 Cases Fine Sheet, Crepe, Biscuits or Block :— 

 Nett 4,480 lbs. @ 5/3* c.i.f. 



£1,185 6 4 

 5 18 6 



Brokerage £ % 



£1,179 8 2 



November, 1906. 



LEWIS & PEAT, 

 6, Mincing Lane, London. 



Experiments in Creosoting and Blocking Wet Rubber. 



By J. C. Willis and M. Kelway Bamber. 



In accordance with a suggestion made by one of us* at the Rubber Exhibi- 

 tion, experiments were commenced to test the possibility of sending home undried 

 block rubber preserved with the aid of creosote. 



It was impossible at the time to obtain the crude creosote in Ceylon, so 

 experiments were made with the pure article. In order to mix this perfectly 

 with the latex, it was first dissolved in methylated spirit, as recommended by 

 Parkint in 1899. 



Acetic acid was added in the usual way, care beiug taken not to add too 

 much, and the latex was rapidly coagulated in a Michie-Golledge machine. 



As soon as coagulation was complete, the mass was cut up, passed once or 

 twice through the washing machinery to remove excess of soluble matter, and 

 then immediately blocked for two or three hours in a wooden mould in a 

 screw press. 



The block so prepared contained from 8 to 9 per cent, of water, but with 

 better fitting moulds and rather higher pressure this might be reduced to 7 per 

 cent, if necessary, and kept fairly uniform. 



A drawback to the rapid coagulation in the above machine is the formation 

 of a spongy rubber, which when blocked does not have a very satisfactory appear- 

 ance. Better results as regards appearance can be obtained by coagulating the 

 rubber in tins or troughs of any length, but of the width or twice the width, of 

 the mould blocks, and cutting this into the requisite lengths or shapes with a 

 sharp knife, and filling the mould with the pieces. 



The troughs should have outlet cocks beneath to run off the water and 

 impurities, and the rubber can be washed without manipulation by half filling 

 the trough once or twice with clean water from a spray nozzle or from below. 



Rubber prepared in this way amalgamates perfectly in the mould, and a 

 homogeneous mass is obtained. 



The blocks rapidly darken on the outside as they dry, and then look and 

 smell very like the block of (South American) fine hard Para exhibited at the 

 Rubber Exhibition, 



Samples prepared in the above manner were immediately taken home 

 by Mr. Brett, one of the Rubber Judges at the Exhibition, and he has just cabled 

 as follows :— 



"Value per lb. 5s. Od. ; containing moisture 9 per cent. ; continue experi- 

 ments ; strength excellent, better than average plantation rubber." 



* "Rubber in the East," p. 223. t Cira, R, B, G., Vol. I., No. 12, 1899 



