DEVELOPMENT OE COAL MINES, ETC.

45

D.—No. i

New Zealand Coal.

B.—For Steam Purposes. Mr. Kebbell's trials were made by burning half a ton of coal, and ascertaining the time a stationary engine was kept at work with the consumption of this weight of coal. Care was taken in each case that the height of water in the boiler, the pressure of steam, the work being performed by the engine, and all other circumstances, should in each case present exactly the same conditions when the trials were commenced and completed. h. m. No. 1. —English steam coal ... ... ... worked engine 4 25 No. 2.—Newcastle, N.S.W.* ... ... ... „ „ 4 39 No. 3. —Collingwood coal, No. 1 trial ... ... „ „ 4 55 No. 4. —Collingwood coal, No. 2 trial ... ... „ „ 5 0 No. s.—Grey Eiver coal ... ... ... ... ~ „ 5 5 No. 6. —Bay of Islands, Kawa Kawa Mine* ... ... „ ~ 5 11 No. 1 gave about tho same quantity and description of coke as tho New South Wales coal. No. 2 made 114 lbs. of waste on the half-ton. Nos. 3 and 4. This coal cokes sufficiently to prevent it running through the bars. If the fires are fed regularly, they require no stoking, and the least attention of any coal ever used by Mr. Kebbell. The clinker is similar in quantity and quality to the New South Wales coal. No. 5, Grey Eiver coal, is a good coking material, and cakes very much in furnaces with a moderate draught, requiring a good deal of attention. The quantity of clinker and waste was so small as not to be worth mentioning. No. 6, Bay of Islands. This coal made 28 lbs. of clinker, which is injurious to the furnace bars, adhering to them very strongly, and can only be removed by allowing the bars to cool down. If it were not for this fault it would be a good steam coal. In these trials all the New Zealand coals give a better result than either English or New South Wales coal, in work performed with an equal weight. Eor household purposes, all who have tried the Grey Eiver and Collingwood coal prefer them to any coal imported into the Colony, as being cleaner and burning more freely and pleasantly. All the expirements made and information that I have been able to obtain tend to show that New Zealand possesses superior coal for steam purposes, when worked with stationary engines, at a moderate draught, and for household and gas purposes, to that of New South Wales; but that for steamers' boilers, working at a strong draught, the heavier coals of England and New South Wales have the advantage. It is to be hoped that the further development of the mines will ultimately remove the last named defect. * Computed from a previous series of experiments, the value of the English coal being taken as the same in both. y

Date of Test. Weight of Sample tested. 6 jf b Pri If O OVl |^«fl o •3 iri p° I £ g S a fl 9 '~ no o 03 a ° o 'j3 o VJ fcD _. a .- ° m a; 1*1 Weight of Coke per Ton of Coal, in lbs. Name of Mine. Remarks. 1871. Apr. 30 Grey Coal, Test No. 1 ... „ Test No. 2 ... 7 lbs. 7 lbs. 35-5 31-3 11,360 10,016 jl'4* 1,590 ( This is not a guaranteed sample ; it was obtained from the s.s. " Luna," and may possibly have other eoal mixed. 3) July 10 July 17 Grey Coal 1 „ f Grey Coal, Slack | Js _ >~» " " " I g | I ° t.w si )> )t )) H JS jtnm L Collingwood Coal (Nelson) 112 lbs. 112 lbs. 550 430 11,000 20 to 24 21 to 25 1,820 The quantity registered is doubtful. July 18 112 lbs. 510 10,200 Average 22J Average 22J 2,020 July 20 112 lbs. 550 11,000 1,880 Retorts were at a much greater heat than in the preceding and following examples. July 24 112 lbs. 530 Average 20 18|tol9 1,800 10,600 Mar. 23 Mar. 31 5) ») )' (3 tests about equal) 7 lbs. 7 lbs. each tons cwt. 8 4 28-27 About 5,000 9,811 18 to 19 1,280 Retort at only a dull red, about 1,000°. Illuminating power ascertained after gas had been stored some time, perhaps two or three days. This gives illuminating power after storage, and as was supplied to consumers. June 30 Collingwood Coal (Nelson) 76,960 9,300 nearly 19 1,780 July 25 j> >> j> 112 lbs. 500 10,000 25 and above 18 to 19 1,500 July 8 Bay of Islands Coal (Kawa Kawa) Mount Somers, Ashburton River, Canterbury 112 lbs. 530 10,600 1,328 July 17 84 lbs. 200 5,300 None A small quantity of light breeze only left after working off the gas.