88 TIN MINING IN PERAK. 



up from time to time as occasion offers ; that is when ilie 

 monitor has to be stopped from want of water or other causes, 

 or when repairs to the shiice boxes are being carried out. 



Shortly after the writer's visit to the mine the wash boxes 

 were duplicated, and it was then possible to use the two -inch 

 nozzle without the tin -ore being carried down the sluice by the 

 increased volimie of water. The men employed on this sluice 

 are twenty -four in number, working in sliifts of eight men. 

 The shifts are four hour ones, so that each man does two sliifts 

 a day. Here the men seem to prefer short shifts to the eiglit^ 

 hour ones customary amongst English miners. The yield of 

 tin -sand from the one sluice was, at the time of the writer's 

 visit, about five tubs a day of twenty -four hours. 



Half a mile away, on the same concession, a second monitor 

 was erected, the water supply for which is derived from the same 

 source as the other and comes down, firstly, in six hvmdred feet 

 of six -inch pipes, and then through eight himdred feet of four- 

 inch ones. These latter are welded and are fastened together 

 with clamp joints. The pipe line is therefore one thousand four 

 hundred feet in length, the fall from the intake to the monitor 

 being about two hundred and fifty feet. Over four hundred feet 

 of sluice, riffle and wash boxes follow the face ditch and the final 

 wash boxes are twelve feet wide, employing three men to catch 

 the tin -ore. With this exception the sluice and the method of 

 working it are the same as that above described. The tailings 

 are carried through a race a quarter of a mile long into the same 

 large river. 



After working satisfactorily for some time the tin bearing 

 earth became so clayey and hard that, with the pressure avail- 

 able, the jet from the monitor would not break down a sufficient 

 quantity in the day to pay expenses. This was very unfortunate 

 for the owners, who liad spent so much time and money in per- 

 fecting the working of the sluices. However, the problem of the 

 adaptation of the gold sluice to the exigencies of tin mining has 

 been solved by them, and it now only remains for someone to 

 apply it in the mining of some suitable land to estabUsh hydrau- 

 lic sluicing on a permanent basis in the Native States. 



The conditions necessary are, firstly, good tin bearing earth 

 of not too hard, clayey or stoney a character. Secondly, a 

 supply of water with a head of from two hundred to five 

 himdred feet. Thirdly, a sufficient fall beneath the land to 

 be worked to allow of the l)uilding of the sluices and. fourthly, 

 an outlet for the taihngs, where they will either be swept away 

 by a large river or fill in worked out land. 



