was required to run quicker, turn the brush frame backwards; if slower, turn it forwards. These changes would involve a small loss of energy. If they considered a steam engine designed to yield 100 horse-power its efficiency would be less when indicating 50 horse-power; the economy would be less than at full load. It was the same with air and with electricity. The starting of compound motors was also referred to. In the compound motor Fig. 3 (page 143, Vol. I.), as ordinarily understood, there were two coils, one a series and the other a shunt-winding. He did not recommend compound-wound motors; he nearly always used plain series-winding. Professor Lupton also referred to the economy of compressed-air plants; but he (Mr. Snell) would like to refer the meeting to Professor Kennedy's recent experiments with the Popp system in Paris. He found that unless air was heated before entering the cylinder, the efficiency was not more than 22 per cent.-the ratio between the horse-power of the air engine and the indicated horse-power of the steam engine was 22 per cent. He thanked the members for the kind manner in which they had discussed his paper. He hoped it would lead to practical results. He thought-and his opinion was backed by many eminent men of the present day-that electricity was the power of the future.

The PRESIDENT said they must all feel very much obliged, not only to those gentlemen who had taken part in the discussion, but to Mr. Snell for the very lucid manner in which he had explained the subject. He (the President) agreed with Mr. A. L. Steavenson that if a fire took place in a mine the circumstances would be most serious. Did not the coal often take fire from other causes? He knew several instances from candles alone, so that Mr. Steavenson's argument might equally be applied to candles. They had had a long discussion, and he hoped at some future period it would be continued, for there were many points in connection with electricity that required very distinct elucidation. He hoped that after this discussion was printed there would be no further delay in publishing the Transactions, and that when the members had read it they would come forward and either offer a paper on electricity themselves or discuss somebody else's paper. He thought it very useful that it was not against the rule for a member to raise at one Institute a discussion upon a paper read at another. They had had some difficulty about this in connection with the Midland Institute, and he had asked the Council of the Federated Institution whether it was proper that these discussions should take place in the way he had mentioned, and was informed that it was perfectly proper, so that now they were at liberty in Yorkshire, Staffordshire, or Nottingham to pull to pieces what the wise people read in Newcastle, with the disadvantage that there would be no personal reply. If the criticisms happened to "touch the raw" of the author he could reply by correspondence, as was done in the Institution of Civil Engineers; thus they would have not an ejective but an objective correspondence, for the author of a paper would not feel very easy if he found in one of their publications a remark that he was totally mistaken in his views respecting something; so one could imagine him saying, "I will correspond with that Institute and give them my mind upon it." With these few remarks he would propose that the thanks of the meeting be given,

in the first place, to those who had taken part in the discussion, and also to Mr. Snell who had been the originator of the discussion; and they would all agree that they were well worthy of the thanks of the meeting.

The vote of thanks was heartily adopted.

Mr. J. B. SIMPSON reminded the members that at eight o'clock in the evening the Principal and Professors of the Durham College of Science would give a conversazione at the College. He begged to propose that a vote of thanks be accorded to them for their kindness. It was not usual to return thanks before accepting a gift, but they might not have an early opportunity of acknowledging their indebtedness to the Principal and Professors of the College.

Mr. JOSEPH MITCHELL (Barnsley) seconded the proposal, and it was unanimously approved.

The SECRETARY having announced the arrangements for the following day, A vote of thanks to the President, proposed by Mr. MILLS, terminated the business of the General Meeting.

DINNER IN THE NEW ASSEMBLY ROOMS.

MR. J. B. SIMPSON, PRESIDING.

After the loyal toasts, the CHAIRMAN proposed the "Federated Institution of Mining Engineers." He was extremely sorry that Mr. W. Cochrane, the President of the North of England Institute of Mining and Mechanical Engineers, was abroad, as that gentleman ought to have taken the chair on this occasion. In Mr. Cochrane's absence the position had been allotted to him, and he only regretted that the toast had not been left to abler hands. As some of the gentlemen present might not be conversant with the details of the work of the Federated Institution of Mining Engineers, he might observe that at present it was a combination of the following Institutes :-The North of England Institute of Mining and Mechanical Engineers, the Chesterfield and Midland Counties Institution of Engineers, the Midland Institute of Mining, Civil, and Mechanical Engineers, and the South Staffordshire and East Worcestershire Institute of Mining Engineers. These institutes had federated themselves for the purpose of holding joint meetings in various districts for the dissemination of mining knowledge, for extending their interests, and that they might appoint committees to report upon all subjects pertaining to mining. These were, he believed, the broad objects with which the Federation was commenced. He was sorry to say that all of the mining institutes had not joined in the Federation, but it was hoped that the day would soon arrive when those institutes would see that it would be to their great advantage and for the benefit of the mining industries of the country that the Federated Institution should embrace all. The institutes, however, in their individual capacity were not to be altered, and they would in their different spheres perform the functions they had hitherto done, and he thought these institutes had good reason to If they congratulate themselves on the success they had severally attained.

went back to the beginning of the present century and considered the state of mining at that time he thought they would come to the conclusion that these institutes and practical miners had developed the coal trade of the country in a very remarkable manner. He happened a few days ago to come across a manuscript of the late Mr. Buddle which would show them the position of mining in the year 1807. Mr. Buddle referred at that time particularly to Wallsend Colliery, with which he was connected. They were probably all aware that in former days, when working in shallow mines, pillars of coal were left very thin, but as the mining became deeper, the pillars of coal were left of the same thickness, the viewers or mining engineers of those days did not know or did not take into consideration the fact that the superincumbent strata were too heavy for these pillars to bear, and the result was that "creeps" were continually taking place, the pillars breaking down and the effect often being felt at the surface. It was on record that at Long Benton Church, when the parson was preaching one Sunday, bits of the ceiling came down, and the people began to be rather nervous. "It's nothing," he said, "it's only the creep in the pit; if you wait a bit it will be all right." But the congregation didn't "wait a bit," they began to creep out. These creeps affected ventilation, too, and the air currents were constantly being reversed. Here were Mr. Buddle's comments at Wallsend Colliery when the creep had upset the ventilation :-" Feb. 13, 1807.-Made some boxes to send some steam into the shaft to warm it with a view to restore the upcast, and got some large pieces of iron ready to heat, which are to be lowered down the shaft to assist the upcast. Feb. 14, 1807.-Applied the hot iron all day in the shaft, but without effect, as it continued to cast down, got the steam conveyed into the shaft, and continued it all night. Feb. 15.-Found the pit casting up this morning, and the following day got the pit to work." Now, all the gentlemen who knew anything about mining would know what a feeble current of air they must have had in those days. Fancy one of the largest and best collieries in the district being in the position of having only 3,000 or 4,000 cubic feet of air per minute! No wonder that explosions were very frequent about that period; so frequent indeed that the public took up the subject, and in 1813 it was recorded that a society was formed in Sunderland for the prevention of colliery accidents. It was taken up by the Duke of Northumberland, the Bishop of Durham, the Rev. Mr. Gray, the Rev. Mr. Hodgson (the historian of Northumberland), Mr. Buddle, by Dr. Clanny, and others. These gentlemen made several reports, and in one Mr. Buddle described the whole of the operations of mining, concluding his report in these words: "I think any further application of mechanical agency in preventing explosions would be ineffectual, and we must look to some method of producing such a change upon carburetted hydrogen gas as to render it innoxious as fast as it is discharged. In this view it is to scientific men only that we must look for assistance in providing a cheap and effectual remedy." Well, these gentlemen did apply to somebody; they applied to Sir Humphrey Davy, and in the course of two or three years, as was well known, they had the safety-lamp invented. This was the beginning of the mining institutes, and after that society had been so successful it

was disbanded, and nothing more was done in the way of scientific mining societies until the year 1852. Then an explosion took place at Seaham Collieries, and a number of engineers-several of whom were still living-founded the North of England Institute of Mining and Mechanical Engineers, which had continued from that time to the present. Other institutes sprang up in the different mining districts of the country, which had done most effective work, and had promulgated a scientific system of mining, which everybody must feel had been of very great advantage to this country. They hoped sincerely that the Federated Institutes would go on still further developing the wonderful art of coal mining. He thought they might still, as their old friends of 1813 did, go to scientific men, and say, "We want something still to prevent accidents, and we want something to increase the economy of working our coal mines." In what way progress would tend he did not know; it seemed to be pointing in the direction of electricity, but whether it would give them an electric lamp which would comply with the motto of their Mining Institute," Moneo et munio," or not he could not say. No doubt within the present century they would have a safe light for mines and we would have electrical tramways for cheapening the cost of conveying the coal underground and probably electric coal-cutting machines. Without further comment, he would call upon them to drink "Success to the Federated Institution of Mining Engineers," and couple with that toast the name of their worthy and venerable President, Mr. T. W. Embleton.

The toast having been duly honoured,

Mr. EMBLETON, replying, said he was not aware until he came to the meeting of the Federated Institution that he was to be their President for the ensuing year, and he must therefore be excused if he had not been able to collect his ideas for such an occasion as the present; but he hoped that during the time he occupied the position of President all the complaints that had been made would be removed, and that the Transactions would be regularly printed and punctually forwarded to each member of the Federated Institutes. They would receive all the papers read before the Federated Institution, and there would be this advantage, that they would find in those papers and in the discussions that would be published, the concentrated knowledge of all the institutes, which, if they were not federated could not be obtained without considerable trouble and expense. People nowadays called for their rights, and it was the right of each member of the Federated Institution that he should have reports of the meetings, whether they were held in Durham, in Yorkshire, in Derbyshire, or in Staffordshire. They would thus know in each district what appliances and improvements they had in the other districts. They would also have the advantage of knowing all that was being done at the home Institute, the originator, and, he thought, he might say the queen of all the other institutes, for it was their parent. He had been a member from the time which he called the year 1, which was a long time ago, and he might say he had not been altogether an idle member, for he had sometimes read little bits of papers which had given some information. The Chairman had recalled the state of mining, or rather of ventilation in the year 1807, but he did not think it had been from

personal acquaintance with mining at that time; in fact he probably had not appeared on the face of the earth at that time, for if he had he would have been two years older than himself. He did not know whether many of them could remember the time when they descended the shaft in the loop of a rope, guiding themselves with a stick to keep off the side of the shaft; he did not know whether even the Chairman was accustomed to that means of going down, but he himself was, and thought no more of it than of getting his dinner here. But where would they find the pitman, or the young mining engineer, who would venture down the pit now, as they used to do in those days? He thought they would not like it; whether their organization was more sensitive than in those days he could not say, but custom was everything, and if they accustomed themselves to a thing they might even come to like it. He remembered when cages were invented and a long time before they were introduced. The first beginning of cages was at a colliery near Sheffield about 1813, and he had a drawing and the specification of it. Mr. Buddle reported upon it. It was an ingenious contrivance, and he would try to describe it. There was a cage in a pair of guides and the rope was attached to the centre of the cage. Things were altogether different now, and if anyone could live for fifty years longer he had no doubt they would find as much improvement, or perhaps greater improvement, than had taken place during the last fifty years, and they would be entirely different from the labours of the members of these institutes; whoever thought of the fan or the many other contrivances? There was another thing; he hoped that as children were all better than their parents-a good deal better-that so the younger institutes would surpass the older. He thought it was only right to infuse fresh blood as the old hands were dying out; he believed there was only one gentleman present who could approach his own age. The old fellows had gone to make room for the young.

The MAYOR OF NEWCASTLE proposed "Success to the Coal Trade." As the representative of the Corporation-and through them of the people of Newcastleupon-Tyne-he was deeply interested in the success of the coal trade of the counties of Northumberland and Durham. Their interests were identical; the welfare of the people, and of the city, was dependent on the prosperity of the trade in which the gentlemen present were also deeply interested. He believed he was right in saying, too, that the Corporation represented probably the oldest coalowners in the North of England; for the Newcastle Municipality, as coalowners, dated back to the time of Henry III., but, unfortunately for them, the royalty under the Town Moor not being recuperative was almost exhausted; they were still, however, interested in a very large royalty at Walker, and were partaking at the present time in the increased prosperity those present were also enjoying, through a large increase in their royalty rents. Being deeply interested in the welfare of this particular trade he had the greatest pleasure in proposing "Success to the Coal Trade," and in coupling with the toast the name of their esteemed friend Mr. R. O. Lamb.

Mr. R. O. LAMB, after acknowledging the toast, said those members of the coal trade who were junior to himself must have felt, as he did, great pleasure in listening to the remarks of the worthy President of the Institution, and he could only assure