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THE use of electricity in mines has become so general that it is unnecessary to dwell upon its advantages for ordinary purposes. Special regulations for its use have been issued by the Home Office, and all candidates for the position of Inspector of Mines have to qualify in electricity as one of the subjects of examination. The operating of main winding-gears by electricity is little practised in England; a few small winders have been put in, and one large one of about 1,500 HP. is now being erected in South '' Winding-Plants for great depths." Transactions of the Institution of Mining

Mr. ,4. H. and cropped up at unexpected points and caused endless difficulties. With regard to the hesitation to adopt high speeds for very large powers, he thought that was a fact. The difficulty which he foresaw with high-speed engines was that the friction losses were likely to be greater than with any low-speed engine through the necessity for a large number of cylinders, and the efficiency was somewhat reduced. I t was very curious that all the large stations in London charged the largest prices, and i t would be found that those large stations in London produced worse results than any other. I t was very interesting to see the great difference between the cost from the figures which Mr. Jones had given for connecting customers with gas-and electric-light. He thought he was correct in saying that with gas companies the connection of consumers and certain works of that kind were very often charged to revenue, and, not as in other companies, direct to capital. It would be generally agreed in London that the regulation with direct current was generally a little worse than with alternating current. He feared that Dr. Kennedy and Mr. Crompton had based their remarks rather upon the measurements taken in the electric-lighting station. The curves given in Figs. 6 had been taken on consumers' premises unknown to the company, and they were affected a great deal by the want of balance ; in fact, the two top lines, which he did not think were very good, belonged to the Westminster Corporation. It wonld be seen that the variation at times was larger than i t should be. With regard to lighting of streets, that was purely a question of cost and an administrative matter, and he did not think he need refer to that. With regard to the plugging of the pipes, which had been referred to by Mr. Patchell, he submitted that it was far better to prevent any gas from entering the pipe-system by plugging the pipes, and that any gas should be confined to the spots where it gained an entrance.