Preserving Mine Timbers. 



On a recent visit to Eossland, B.C., 

 Prof. John Macoun, naturalist of the Can- 

 adian Geological Survey, visited a number 

 of the mines of the place, with a view 

 to studying the cause of the rotting of the 

 mine timbers and possible means of pre- 

 venting it. In the Central Star mine he 

 obtained specimens of four species of 

 the genera Polyporus and Trametes, which 

 include many of the fungi most injurious 

 to wood above ground. 



Of the means to be adopted to pre- 

 serve from decay timber used in the 

 mines. Prof. Macoun writes as follows: — 



In conversation with the manager of 

 the mine, I suggested painting the posts, 

 as the spores of the fungus must enter the 

 wood to produce injury. I mentioned the 

 methods adopted in the United States, and 

 spoke of creosote, but really all these 

 methods mean the same thing, the keep- 

 ing of the spores out of the wood, because 

 there can be no rot without fungus or 

 algoid spores. 



Since my return, the Director has men- 

 tioned a statement made by Mr. Watson, 

 one of the mining engineers from Europe, 

 that timber used in mines there has been 

 preserved by immersing for a time in a 

 strong saline solution before being used 

 under ground. This I consider a complete 

 solution of the difficulty, as no fungus 

 is known by me to grow on trees or other 

 woody matter which is found lying on the 

 seashore. All wood on the seashore is 

 sound, and all wood on the borders of 

 lakes or rivers is rotten. A detailed de- 

 scription of the method referred to above 

 follows: — 



A method of treatment of timber, known 

 as the Henry Aitken method, is now used 

 at many collieries. In this process the 

 idea is to soak the timber in water, rais- 

 ed to a temperature of from 190° to 200° 

 Fahr., containing enough common salt to 

 form a thoroughly saturated solution. The 

 timber should be free from bark, fairly 

 well seasoned and thoroughly dry. Any 

 tank, either wood or iron, of a size suit- 

 able to contain the timber to be treated 

 will do "and the water should be heated. 

 The time necessary for completing the 

 process depends largely on the nature and 

 size of the timber, but two days will, in 

 general, be sufficient. By sawing off a 

 small part of the timber being treated, 

 it can be seen whether thorough penetra- 

 tion by the salt has been obtained. When 

 the timber is removed from the treating 

 tank it is soft and not in a condition for 

 immediate use. It is dried by being put 

 into a covered shed or stacked in the open 

 air. The cost for treating timber bv this 



process averages, in Great Britain, about 

 one penny per cubic foot. 



Some of the managers of the largest 

 collieries in Scotland, who have adopted 

 the process, write as follows:— 



Mr. Maevie, manager Cadzow collieries, 

 Hamilton, regarding the Aitken process 

 for treating the timber for use in mines, 

 states that in his five years ' experience 

 he had never seen the least indication of 

 decay in any timber so treated. About 

 four years ago, gears (every alternate one 

 treated) were put in the main return air- 

 way of the No. 3 Pit Ell coal seam, Cad- 

 zow colliery. About a year ago all the 

 untreated gears were replaced, owing to 

 decay. The treated timber is still in use 

 and in good condition. As regards the 

 contention that the Aitken process re- 

 duces the strength of the timber, he had 

 never seen anything to make him think 

 that this was the case. Indeed, he had 

 stopped using larch timber, and now used 

 treated Scotch or foreign fir. 



Mr. Ferguson, manager Benarty col- 

 liery, Fifeshire, writes that the Aitken 

 process has been in use at the Lochore and 

 Capeldrae collieries for upwards of six 

 years, and during that time it has proved 

 a great saving, not only in wages renew- 

 ing broken timber, but also in the price of 

 wood used, which is now nearly all for- 

 eign timber. The treated wood had stood 

 in the return airways for six years and 

 was quite sound. If this wood had not 

 been treated it would have been replaced 

 twice during the above period. No tree 

 which had been treated had shown the 

 slightest decay during the six years. 



Mr. Carlow, managing director Fife 

 Coal Company, Leven, Fifeshire, writes 

 that the Aitken process had been in use 

 for four years. 



The following experiments have been 

 made with the process: Two pieces of 

 ordinary fir, three and one-half inches in 

 diameter and three feet long, both weigh- 

 ing ten pounds before treatment, were 

 selected. One of the pieces was treated 

 by the salt process and the other was not. 

 After being treated, the former weighed 

 twelve pounds. Both were taken under- 

 ground and placed in a. return air-course, 

 and after eleven months were examined 

 and re-weighed. The untreated timber 

 then weighed five pounds only, whereas the 

 treated one weighed twelve pounds, being 

 exactly the same weight as when it was 

 put in. They were put back into the mine 

 and allowed to remain eleven months 

 longer, with the result that the untreated 

 timber weighed six pounds and the treat- 

 ed timber weighed eleven and three- 



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