now possessed, were made when the mines were first opened up, which will inevitably entail serious loss in the future; as an instance, much valuable ground is now seen to be covered up by the dumps, which will unquestionably have to be moved presently when the land is wanted for working.

The same want of foresight, for which there was less excuse with the Thetford experience to guide them, will inevitably cause trouble in the near future at Black Lake, on the property of the Anglo-Canadian Company, even to a more serious extent. The parties who first opened up the ground here evidently knew what they were about, but their immediate successors, being destitute of all practical mining knowledge, have, by their neglect of professional assistance, committed such errors of judgment as will presently occasion very serious expense to the company. At their main pit many thousands of tons of waste rock have been dumped on to some of the richest part of the ground, and this must be again moved before that ground can be worked. From the peculiarity of the work, there probably exists no class of mining which so absolutely necessitates the services of a practical mining engineer, in marking out the land in the first instance for mining and dumping, as that for asbestos does.

The cost of extraction varies in different localities, depending mainly on the mass of barren rock to be encountered and removed. At Thetford the cost may be put at from $20 to $25 per ton, the latter probably being nearer the average. On the Anglo-Canadian Company's property at Black Lake it is a more serious matter. There the quantity of barren overlying rock and earth is enormous, and detracts immensely from the value of the mines. The minimum cost here is $28.

In addition to asbestos, it is worthy of note that the whole of the Thetford district is rich in minerals. Among others some large and valuable deposits of chromic iron are found in the immediate neighbourhood, within but a short distance of the asbestos mines.

THE COLERAINE GROUP.

Four miles farther down the line of railway from Thetford we come to the Coleraine group of asbestos mines, situate at Black Lake.

The pioneer of these mines was a Mr. Noel, now resident at Richmond, near Sherbrooke, in the same province, who, in 1881, discovered and opened up a mine of a promising character here, which in 1882 he sold to Mr. Charles Lionais, who was until recently the resident manager of the mines owned by the Scottish Asbestos Company, at Black Lake and Broughton.

The mine first opened here was called by Mr. Lionais the "Eureka," and some time afterwards he opened another on the same estate which he named the "Emelie." The property on which these two mines are located subsequently came into the possession of the late Mr. Sénécal, and was by him transferred to the "Anglo-Canadian Asbestos Company, Limited," on the formation of that company in London, in the autumn of 1885.

The estate owned by the Anglo-Canadian Company comprises 325 acres, and has a frontage of 1,350 feet extending backwards over the hills as far as Lake Cariboo. Until recently this was the only place in the district where machinery was employed to get out the ore.

The peculiar characteristic of this property, as distinguished from the mines forming the Thetford group, is that much exceedingly heavy work, necessitating of course great expense and showing very poor results, must of necessity be done before the good veins, if any such exist, as it is believed they do, are reached. Much of this has already so far been done at the Emelie, that at length this portion of the property bids fair, in capable hands, of proving to be a moderately paying mine. Great results were prophesied from it at first, but so far it has by no means realised expectations.

The surface veins, not only at the "Emelie" but all over the property so far as yet proved, are not only thin, but are much discoloured by the infiltration of water which is so strongly impregnated with the oxide of iron as almost to destroy its value. It was thought, and as it would appear with some show of reason, that the output would greatly improve in value as a lower depth was reached; but although there has undoubtedly been a sensible improvement in quality, the general result is disappointing. Started as a No. 3 mine, as such in all probability it will continue. The output from this Company's mines for 1886 was 330 tons.

The No. 3 quality of asbestos, which has hitherto been the main produce of this mine, fetches so low a price in the market that alone it would not pay for working. This, as already explained, is mainly on account of its bad colour and general coarse quality. This latter having somewhat improved, a considerable proportion of the produce would cease to be classed as No. 3 if it were not for the bad colour. It therefore occurred to me that it might be possible to remove this defect without injuring the fibre, and in consequence I had some experiments made with this object in view, and ultimately succeeded beyond my expectations, in replacing the discoloured fibre by one sufficiently bright to enable it to take rank as No. 1. These experiments, it is true, were only conducted on a limited scale, but, so far as I am aware, there is no reason why it should not be done on a large scale, which would very materially increase the value of the article.

There is ample room for opening up in a more judicious way on other parts of this property on what seems likely to be good paying ground; and a mode of doing this without incurring any further expense might easily be devised, and, if this were done, other seams of better quality might be hit upon.

Another point in the company's favour is that, if judiciously selected, there is abundant room for dumping without encroaching on the ore-bearing grounds—a most important matter when consideration is taken of the enormous quantity of waste rock to be here encountered and removed.

The buildings on the estate are well constructed, and are in an efficient state of repair, but at present there is an insufficiency of dwelling-houses on the property. These are a necessity in the district, for securing and retaining a better class of labour. No great expense would have to be incurred in supplying this deficiency. Lumber and labour are both comparatively cheap, and the buildings in themselves, moreover, would always return a fair interest on the outlay.

The property on which the "Martin" Mine is located closely adjoins the last mentioned. This has recently been acquired by "The Scottish Asbestos Company," of Glasgow, with the intention of working it in conjunction with their mines at East Broughton. Judging by the elaborate preparations for work which are being made, and the expenditure which is being incurred in buildings and machinery, it is evidently the company's intention to carry on work vigorously in both places.

Their property at Black Lake covers 102 acres, and is described as being a mile long by 520 feet wide. The output is given as 300 tons, but I should doubt very much if it has yet reached this figure.

The ground here and in front of the Anglo-Canadian Company's land rises very rapidly, from the level of the Quebec Central Railway, until it attains a height of nearly 600 feet, being then about on a level with the Thetford mines. The great serpentine belt crosses both properties, and is bounded along its northern margin by quartzose granulite, separated from the serpentine by a narrow belt of soapstone. It is claimed for property of the Scottish Asbestos Company, that not less than three-quarters of it consists of the rock formation that seems to be the asbestos matrix.

This property is well laid out, and has a considerable number of dwellings already erected on