DISCUSSION ON MR. HARGRAVE WALTERS' PAPER ON "AN EXPERIENCE WITH EXPLOSIVES USED UNDERGROUND;" MR. M. WALTON BROWN'S PAPER ON "EXPERIMENTS WITH EXPLOSIVES USED IN MINES;" MR. F. S. MARSH'S PAPER ON "GERMANS (FUZES);" AND MR. T. M. W. WALLIS' PAPER ON "THE LOW TENSION SYSTEM OF SHOT-FIRING."

Mr. HARGRAVE WALTERS (Birley), said he would like to state that since writing his paper, which was something like three-quarters of a year ago, in consequence of so much delay in publishing the Federated Transactions, there had been a number of experiments with explosives, followed by discussions, in different parts of the country. Therefore, whatever value the paper possessed before, it had been considerably shorn of its interest, although most of his own statements were borne out by the later experiments.

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Mr. A. H. STOKES thought the question a very important one, and one which ought not to be lightly discussed and dismissed. Indeed, before the discussion closed, he would like to have the last paper named on the agenda in the hands of the members. Mr. Walters' paper had been delayed, but it was none the less valuable for that. As regarded explosives in mines, he did not think they had one which was absolutely flameless. With respect to the future explosives, there was a great opening for the chemist to give them one which, under any conditions, would be flameless. He had read of a new explosive which had been tried in France. It consisted of 80 per cent. of nitrate of ammonia and 20 per cent, of dynamite. It was not a strong explosive, but sufficiently strong for the miner. It exploded at a temperature much lower than that necessary to ignite fire-damp. In strength it was something between a lime cartridge and dynamite. He did not know if it had been seen or tested in England, but if they could get such an explosive it would be of very great value. As to germans and fuzes, he presumed it was not generally known that gunpowder fuze at the moment of striking would ignite gas. Yet they had people using supposed flameless explosives or water cartridges, and firing the same by a fuze that would ignite gas should there be any near the hole at the time of firing. Some persons were most particular with regard to opening a safety-lamp to fire a shot (and quite right too), but at the same time overlooked the danger from the use of gunpowder fuze. It was very questionable whether shots that were fired in a mine in which safety-lamps were used ought not, in future, to be fired by electricity. The germans mentioned by Mr. Marsh were sometimes as erratic and lively as a real German. They occasionally flew all over the place, and they were uncertain in the firing. Numbers of accidents had occurred from their use. Mr. Coroner Browne investigated this question some time ago. He condemned them after holding enquiries on men whom he thought to have been accidentally killed from using germans. He did not wish to discuss this matter further at present, but would much like to hear the opinion of others present. He

hoped the discussion on the papers would not be closed until they had the other paper before them. The importance of the subject they could gather from the fact that in his district there were more than two million shots fired every year; and in Great Britain there were more than twenty million shots fired yearly in mines. In reply to Mr. Jackson he could not say what was the percentage of accidents resulting; there were some, certainly.

Mr. H. BROWNE said with regard to the inquests referred to by Mr. Stokes, they also enquired as to the explosives, including coal dust. He thought it was largely owing to societies like this, that the importance of explosives had been recognized. It was one great difficulty they had to contend with. When, as Mr. Stokes told them, twenty million shots were fired per year, it seemed creditable to the management of the mines that they had so few deaths.

Mr. H. WALTERS suggested that there should be some independent experiments. Most of the experiments which had been made had been conducted by agents for the sale of particular explosives, and each of course made the best of his own explosive.

Mr. STOKES-Can Mr. Walters tell us of any explosive that is flameless? Mr. H. WALTERS said he did not know of one. From his experience he had not seen one. There was in his opinion far more danger to be apprehended when bringing the coal down from igniting small jets or quantities of gas in breaks or slips behind the fall and setting fire to the coal, than of direct explosion. But with very ordinary care it was possible to continually blast with the more modern explosives without risk of explosion, and he did not think there should be much difficulty in producing a safe explosive, considering what has already been achieved. The greatest danger will be from heat and not flame. He had seen red hot coke and charred coal at the base of the hole after a shot had been fired.

The PRESIDENT said that was the drawback which many experienced people who had tried several kinds of explosives, to his knowledge, met with.

Mr. W. SPENCER thought Mr. Stokes' suggestion that the matter should be adjourned and not concluded that day, a good one. He had not had as much experience as some people in that room with the new explosives, but he found roburite very good, and he had never seen a spark from it, nor from the water cartridge of Messrs. Nobel & Co. Mr. Stokes said there was no flameless explosive, and Mr. Walton Brown, Secretary of the North of England Institute, and Mr. Walters, both of whom had experimented largely, agreed with him. This was a very important subject and well worth further experimenting upon.

Mr. H. WALTERS said he did not know whether any gentleman there had noticed an account in the Colliery Guardian of last week of some experiments with roburite and several other explosives. To try and explode roburite without tamping was said to be not a fair test; it would, however, represent a blown out shot, and it was quite possible a man might forget to ram a hole. In these experiments flame came out 6 or 8 feet, although roburite was said to have no

flame. If properly rammed it would do its work properly, there would probably be no flame from it, and just the same with any other explosive.

The PRESIDENT said he was in Cornwall two or three years ago and saw the Dolcoath Mine. One of the things which struck him very forcibly was the apparent absence of ventilation in this mine, which was 830 yards deep, and yet they blasted largely with nitro-glycerine. Captain Thomas told him that any stranger entering the mines had intense headache, as the result of the fumes acting on the brain. He happened to be there when the Cornish Mining Institute was holding its annual meeting, and he saw many experiments conducted with roburite. He had not heard whether it had since been used in Cornwall, but so far as collieries were concerned he had read that one of H.M. Inspectors of Mines had expressed the opinion that roburite was flameless. He might be mistaken, but he thought it had been so stated. He had taken more interest in this subject quite recently, as he had been getting up evidence preparatory to being examined by the Coal-dust Commission. He saw that the Prussian Commission had gone into the question very fully, and the Council of the Federation had agreed to accept and publish a translation of the Report of the Prussian Fire-damp Commission; he need not say that would form a valuable adjunct to their Transactions.

Mr. J. W. EARDLEY said last year he saw some experiments at the roburite works with roburite and gunpowder. Roburite had no flame, but the other had.

Mr. T. M. W. WALLIS (Derby) said some experiments had been made in South Wales, conducted, he believed, by Mr. William Galloway. The conditions were made to represent a blown out shot. The explosive to be tested was placed in a boiler with one end open; this was filled with gas and coal-dust, which were mixed by a fan. The most successful preparation was carbonite, which only once flamed, and this exception was said to be explained by an unfired portion of another explosive being left in the hole.

Mr. JACKSON said that many years ago this Institution undertook an enquiry into the effects of coal-dust, etc. The result was a volume of statistics which was exceedingly valuable for reference, and which had been commented upon by the highest authorities. They were told there were many million shots fired in this district every year, that with these shots there was flame, and that if there was gas an explosion would take place. He therefore thought it was for that Institution to take into consideration the suggestion of Mr. Walters, and organize a series of experiments, which should be conducted free from any bias or consideration, other than to find out the best and safest explosive. He for one should be very willing to see some of their accumulated funds expended upon such an important investigation,

Mr. MILLS questioned whether the investigation of this matter had not better come from the Federated Institution. It would be a very expensive affair, for it was no use entering upon it unless they spent a considerable sum. They might put it as a recommendation from that meeting.

The PRESIDENT thought Mr. Mills' suggestion a very good one, and was not at all

sure but that Mr. Jackson's suggestions were equally good. They could easily conduct experiments similar to those conducted in Chesterfield with coal-dust. These experiments cost about £60, exclusive of the cost of publication, and they were very valuable indeed. He considered that his being called to give evidence before the Coal-dust Commission last week was mainly because this Institution obtained such valuable results by their experiments, and in his remarks before the committee he based his statements mainly on the information derived from these experiments; that showed what he thought about their value. They had two suggestions before them, but there was no definite proposal. If someone would make a proposition, and someone else second it, he should be glad.

Mr. JACKSON moved that it be a recommendation from that meeting that the Council should take the matter into consideration and report thereon.

Mr. STOKES said he would like to make a third suggestion. The North of England Institute had published a translation of a number of experiments on explosives which had been carried on in France. It would be a pity if they were to waste time by going over ground which had already been traversed, and he would therefore suggest that before they took any steps they should ask the North of England Institute to allow the translation to be published in the Transactions of the Federated Institution.

The PRESIDENT said Mr. Stokes's suggestion need not interfere with Mr. Jackson's motion. Both could be taken into consideration by the Council.

Mr. J. B. SMITH seconded Mr. Stokes's proposal. As many of these experiments had been already often made it was no good repeating them ad nauseam and getting the same results. They wanted to break new ground. If they got these results and studied them, then they could experiment with some other explosives which had not been tried, such as cordite, etc., which was a class of explosive only used for guns as yet. He believed that from this class of explosive the desired results would be obtained.

Mr. JACKSON agreed to his suggestion being included with Mr. Stokes's and the proposition was carried nem, con.

The discussion of the four papers was adjourned, and

The SECRETARY was instructed to communicate with Mr. Walton Brown in order to bring the approved suggestions, as above, before the North of England Institute and the Federated Institution.

DISCUSSION ON MR. G. E. SMITH'S PAPER ON "THE S.C.P. MINER'S ELECTRIC SAFETY-LAMP."

Mr. G. E. SMITH (Nottingham) said he was sorry not to be able to bring the lamp before them; he had done his utmost with the makers, but they had not sent him one for to-day's meeting. The paper he had the honour of reading before the Federated Institution in September last was not for the sake of advertisement, in

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the meaning frequently given to that word, but for information; not only to give information to them, but what perhaps might be thought a more selfish motive-to obtain information from them as to what they considered an electric safety-lamp for miners ought to be. There was an impression abroad, judging from some of the press notices, that electricity was not a reliable agency in mining. He wished to say that if the same periodic attention was given to electric apparatus that was given to other machinery, they would find electricity not only reliable but a good and useful servant when properly treated. As to this lamp, he had determined not to bring it again before them for inspection until it was complete and had been practically tested by the makers and himself, and he had told the makers so. His desire was to see in the hands of the miners a thoroughly practical and reliable electric safety-lamp, whether an S.C.P. or any other make.

The PRESIDENT alluded to a new lamp which had just been brought out. It had an accumulator, weighed 4 lbs., and cost 14s. He did not know whether the maker would be able to supply lamps at that price. There was some difficulty until the Edison and Swan patent rights expired next year. Until that time arrived there could not be any great reduction in price. Their royalty amounted to about 3s. a lamp, which would have to be renewed three or four times a year.

The PRESIDENT said, he might, however, suggest with reference to the next meeting which it was proposed to hold in the neighbourhood of Alfreton, that they should arrive at Alfreton Station at 8 a.m., and see the Blackwell Colliery Co.'s pits there, and go by the 8:38 train to Teversal. They would there see Silver Hill and Teversal Collieries, and go on at 11:36 to Pleasley Colliery, where cold lunch would be provided. Leave Pleasley 1·42, and arrive at Rowthorne Station 1:48. They would have time to see Hardwick Hall, and leave Rowthorne for Chester. field at 518, or by the 616 to Mansfield. Mr. Hendy had kindly undertaken to write a paper descriptive of the plant they would see during the day, and he hoped this paper would be in the hands of the members before October 21st.

Mr. J. C. B. Hendy's paper on "The Stanton Ironworks Company's Collieries " was taken as read.