1206 THE COLLIERY GUARDIAN. June 14, 1918. MEAN MAGNETIC DECLINATION at Kew Observatory, Richmond, in Degrees and Minutes, for each Two-hour Interval in the Week June 2 to 8, 1918. Magnetic character. Intervals—Hours G.M.T. 0h.-2h. 14° + 2h.-4h. 14° + 4h.-6h. 14° + 6h.-8h. ’ 14° + 8h.-10h, j 14° + ■ 10h.-12h. j 14° + 12h.-14h. 14° + 14h.-16h. 14° + ! 16h.-18h. 14° + 1 i 18h.-20h. , 14°+ 1 i 20h.-22h. 14° + i 22h.-24h. ; 14° + Mean for day. 14° + Min. Min. Min. Min. Min. 1 Min. Min. Min. Min. Min. Min. i Min. Min. Sun., June 2 0 51 *5 50*5 48*5 i 46’5 47*0 I 52 1’0 57’5 57'0 53 ’5 52’5 I 52 1’5 I 52 ■0 : 52’0 Mon., 3 0 51 >*5 49*5 47*5 ! 46*0 47*0 52 1’5 55’5 55 ’5 53’0 52 ’5 52 ’5 , 52 •o 51’0 Tues., >> 4 0 51 .‘5 50*5 48*5 ! 47*0 49*0 54’5 59’5 58’0 54’5 52’5 51 • 5 5. ■0 i 52’5 Wed., 5 0 50’0 50*0 48*5 46*5 47’5 ! 56’0 60 >’5 59 55’0 51 •5 ! 52’0 52 ’5 52’5 Thur?., 6 0 52*0 50*5 48*0 1 47*5 47’5 ! 55’0 61 ’0 59’5 54’0 51’0 1 51 • 5 * 52’0 ; 52’5 Friday, 7 0 50*5 49*0 46*5 ! 45*5 48’0 55’5 59'5 58’0 53’0 50’5 51 •o I 52 •o 51’5 Sat., 8 0 52’5 51*0 48*5 47*5 49 i’5 55’5 61 •o 57 ’5 i 52’0 i 50’5 51 ’5 51 o • 52’5 1 Mean value for Diurnal in e- Ih. 2h. 3h. 4h. 5h. 6h. 7h. 8h. 9h. lOh. Uh. 12h. 13h. 14h. 15h. 16h. 17h. 18h. 19h. 20h. 21h. 22h. 23h. 24h. month. quality (i.e., Junel918 -1*2 -1*2 -1*4 -2*1 -3*8 -5*5 -6*5 -6*4 -4’9 -2’3 + 1’5 + 4’7 + 6’5 + 7’4 + 6’5 + 4’7 + 2’8 + 1’2 + 0’3 + 0’4 + 0’2 + 0’1 -0’2 -0’8 14° 59' ’ 7 June’18 departure from May 1918 —0*7 -1*0 -1*3 — 2’2 -3*2 -4*4 -5*5 -5*3 -3’9 -1’1 + 2’5 + 5’3 + 6’5 + 6’3 + 4’8 + 3’2 + 1’7 + (■’4 -0’3 -0’4 — 0’4 -0’2 -0’3 -0’5 »4° 51''6 May’18 mean value for day) May 1917 -0*4 -0*2 -0*6 -1*3 -2*9 -4*5 -5*0 -4*9 -3’3 -1’0 + 2’6 + 5’0 + 6’4 + 5’8 + 4’0 + 2’5 + 1’2 + 0’1 -0’1 -0’4 -0 9 -0’9 -0’6 -0’8 15° O'’6 May’17 The day is counted from 0 h. (midnight) to 24h. (midnight) Gr.M.T. Character “ 0 ” means a day wholly free from any but small disturbances. Character “ 1 ” means a day part or all of which is moderately or considerably disturbed. Character “2” means a day part or all of which is highly disturbed. The normal value for an hour is the mean declination for that hour in the month, derived from quiet days only, or from all days excluding those of character “2.” On a day of character “ 0” declination at any hour will usually be within about 3' of the normal. On a day of character “ 1” the departure from the normal will usually not exceed 5', but it may occasionally be as much as 10', or even more. On a day of character “ 2 ” the departure from the normal will seldom exceed 20', but departures of 30' or even on extreme occasions of 1° or more may occur. The above values were obtained from measurements made after “ smoothing” the curve. Meteorological Office, June 12. men penalised, arid unless remitted by the end of four weeks from date of deduction shall be handed over to some fund at the works where the offender is em- ployed to be used for the benefit of the workmen or their dependants, or be handed over to some agreed- upon local charity. 9. The regulations herein shall apply by agreement to all workmen members of the Cleveland Blast- furnacemen’s Association. Any workman outside the Cleveland Blastfurnacemen’s Association, and em- ployed at the ironmasters’ works, may submit his case for judgment to the committees if he so desires and be bound by the decision given. 10. Each employer party to this arrangement shall authorise one of his clerical staff to act as secretary to the works committee, and such person shall keep a record of the decisions given by the committee for the particular works, and shall transmit at the end of each calendar month a record of such decisions to the secretary of the central committee and to the secretary of the Cleveland Blastfurnacemen’s Asso- ciation. 11. The committees under this scheme shall exist so long as the munition tribunals under the Munitions of War Act continue to operate, but the regulations may be varied at the end of six months on the appli- cation of either party hereto. 12. The requisite agreements to be made imme- diately by the two associations concerned for enabling the committees to exercise the powers and perform the duties specified above. 13. The Arbitration Act, 1889, shall not apply to any proceedings under this agreement. Signed on behalf of the Cleveland Ironmasters’ Association. J. T. Atkinson, Secretary. Signed on behalf of. the Cleveland and Durham Blastfurnacemen and Cokemen’s Association. Thos. McKenna, Secretary. Middlesbrough, July 24, 1917. Note on Working of these Committees. It is agreed on both sides that these committees have worked very satisfactorily; both employers and em- ployees regard the works committees as a far better means of investigating and settling questions of this character than that of taking the men before the munitions tribunals. Some twenty-eight committees, all of them joint in membership, have been set up, but it has not been necessary for all of them to meet. The central committee had not met up to the end of January 1918, though two or three cases had been recently filed for that committee. A works committee is generally unanimous about its decision—whether or not a fine should be imposed, or the amount of the fine. In a large proportion of cases, more than half, a reduction or remission of fines has been allowed in accordance with section 6 (/). Those workmen who are not members of the union usually avail themselves of section 9 of the agreement to submit their cases to the works committee. THE TIM-PLATE TRADE. Liverpool. Business has been rather slow the last few days. The fall in block tin has brought the official maximum price down to about 32s. to 32s. 3d. per basis box, net, f.o.t. at works, and transactions lately have generally been made at round 32s. Most of the makers now seem to be comfortably booked up over the next two or three months, and they are not very anxious to sell further ahead. Wastes continue in good demand, top prices being realised in most cases. OBITUARY. A gentleman very widely known in the coal trade and general commercial circles Mr. D. P. Richards, at one time, private secretary to the late Lord Merthyr—died on Friday at a nursing home in Cardiff, after an operation. For some years he acted as representative for Sir George Elliot and Company’s wire rope works. His father was manager of the Lewis Merthyr Collieries. The death is announced of Mr. D. W. Thomas, manager of Messrs. D. Davis and Sons, No. 5 pit, at Ferndale, he having been with the firm for over forty years. He was 67 years of age. Mr. John Hanlon, miners’ agent, Whitehaven, died- on Friday last. He formerly worked as a miner in the White- haven Collieries, and was appointed local agent for the men about 14 years ago. INSTITUTION OF MINING ENGINEERS. LONDON MEETING. The 69th general meeting of the Institution of Mining Engineers was commenced yesterday (Thurs- day) in the Rooms of the Geological Society, Burling- ton House, London, W. Mr. Wallace Thorneycroft (president) occupied the chair in the earlier part of the proceedings, and Sir William Garforth afterwards. The members present included Sir Henry Cunyng- hame, Prof. E. L. Hummel, Col. Blackett, Messrs. John Gerrard, J. Simpson, A. Richardson, F. R. Simpson, G. Blake Walker, W. D. Lloyd, D. M. Mowat, G. Graham, J. Robertson, H. Eustace Mitton, A. J. A. Orchard, C. C. Leach, W. D. Lloyd, E. S. Wood, H. Atherton, J. Crankshaw, G. Balfour Sneddon, G. L. Kerr, T. W. H. Mitchell, S. A. Smith, T. F. Winmill, J. Elce, H. B. Nash, B. Madew, C. C. Ellison, J. I. Graham, W. Maurice, S. Hare, H. C. Ross, and others. The meeting adopted the council’s resolution of regret regarding the death of the Duke of Northum- berland, a member of the institution. The President announced that Mr. G. Blake Walker had been nominated as president for the en- suing year, and would assume office at the September meeting. Mr. Blake Walker was well known to them, and he (the president) felt sure that the appointment would be regarded as a most acceptable one. Turn- ing to another matter, the Institution Medal had been awarded to Mr. C. E. Rhodes. A less agreeable sub- ject was that of the conviction of Mr. Arnold Lupton for having a certain pamphlet in his possession. The council had decided that he should be expelled from membership and his name erased from the register. Several members had received honours lately, and he (the president) congratulated Prof. Cadman, who well deserved the honour of K.C.M.G. Col. Blackett had been appointed Deputy Lieutenant of the County of Durham. The ex-president, Sir Thomas Holland, had been awarded the Grand Cross of the Victorian Order, and also the distinction of K.C.S.I. They appreciated the services which Sir Thomas had rendered to his country. Terrestrial Magnetism and Mine Surveying. Dr. C. Chree, superintendent of Kew Observatory, read a paper on “ Terrestrial Magnetism in Relation to Mine Surveying ” (p. 1193), illustrated with lantern slides. Discussion. Mr. T. G. Booking (Birmingham), in a written communication, said he would like to emphasise his appreciation of Dr. Chree’s work, as the ensuing re- marks might give the impression that the import- ance of the paper was not recognised. Underground surveys were often hopelessly inaccurate, and he hoped that the information now given would enable surveyors to rescue some of their surveys from the scrap heap. The paper ought to convince surveyors of the absolute unreliability of the magnetic needle as an aid to the preparation of accurate mine plans. In days when workings were not extensive the amount of error was inappreciable, but now the case was different. In many modern collieries, owing to the electrical equipment, the use of the needle was quite out of the question. The position of all underground routes should be correlated with the surface by theo- dolite surveys. The magnetic needle was relied upon for filling in local work where an error or unreliability amounting to several minutes would have no marked effect. Where the magnetic needle was used, he found it advisable to take the bearing of the surface base line at frequent intervals, and to plot the results as ordinates on squared paper. He was afraid that the work of the Kew Observatory in the present matter would be more of academic than practical interest. In his opinion the magnetic needle should be rele- gated to a subsidiary place in the equipment of mine surveying, and he looked to the time when the mine surveyor would find the needle only in the museum of antiquities. Col. Sir C. F. Close (Ordnance Survey Department, Southampton), in the course of some written com- ments, said that, from the surveyor’s point of view, the most valuable sections of the paper dealt with the magnetic declination. In particular the informa- tion .relating to diurnal variation would be found useful, and also the table giving the secular change of declination for the fifteen years from 1901 to 1916. Dr. Chree had not mentioned the more recent survey by Mr. G. W. Walker, the results of which were be- coming valuable. Mining engineers who desired to use the latest values could not do better than take Mr. Walker’s declinations. Prof. Huaimel said it was desirable that surveys should be as accurate as possible from shaft to boundary, and even boundary pillars should be re- duced to the smallest dimensions, if not entirely removed. He thought it would be well if magnetic observatories could be made available in each mining district to serve mining surveyors in their respective areas. It would be interesting to hear from Dr. Chree whether he thought the number of magnetic observa- tories in Great Britain was sufficient, and whether they were sufficiently near the mining districts for their records to be used without difficulty by mining surveyors, or whether additional ones should be estab- lished. A serious disturbing factor in precise mag- netic orientation was the increasing use of electric installations. These necessitated electric cables along the underground routes, with the result that they interfered with refined magnetic orientation. The presence of electric car services and cable systems over- head would also probably be a disturbing element. It would be interesting to learn the precise extent of their influence. Mr. H. Eustace Mitton said that in the midland counties, as far as the mining profession was con- cerned, he thought that, instead of turning their attention so much to the question of diurnal variation, they ought to see to the manner in which the mining plans in this country were generally kept. In one instance a surveyor mentioned that an extraordinary disturbance of over a degree occurred on a given date, on which he had made an important survey. He thought that the best course was to say nothing, and so far as was known nothing more was ever heard of the matter. Col. Blackett spoke of his long experience in con- nection with mining work, and said he thought that surveyors in his part of the world were not going to trouble about observatories or observers. Mr. Gerrard remarked that the result of 54 years’ experience taught him to rely as little as possible on the loose needle. Many years ago, at the mines with which he was connected, errors were supposed to exist in a large set of plans. A new man came and said all the plans were wrong, and as it was im- portant, by reason of approaching boundaries, to ascertain the facts, he said he would have surveys made to find out the error. Every night for months he was engaged in seeking for the supposed errors. Finally they arrived at the conclusion that the plans were correct. Then they determined to use the loose needle as little as possible, and his (Mr. Gerrard’s) experience went to show that that was the right view. At the same time the institution ought to welcome such a contribution as that of Dr. Chree’s. They ought to be alive to all the changes. For accuracy of survey work let them use the theodolite and dispense with the loose needle as much as possible. Dr. Chree, in reply, said he was not an engineer, but he thought it was well that the information indi- cated should be at the disposal of engineers to enable them to make as good a use of it as possible. It was desirable that they should know all the points of the subject. In presenting the paper, he disclaimed any special knowledge of underground conditions. He was not in a position to deal with the number of observatories in this country. Observatories for scientific purposes would be best located in the most northerly portion of Scotland, the Orkneys, or Hebrides. Artificial sources of disturbance were a great source of trouble near any great centre. A vote of thanks was given to Dr. Chree. Dr. J. S. Haldane read a paper on “ The Effects of Dust Inhalation ” (see p. 1207). The meeting was resumed this morning (Friday). The agenda includes two papers, “ The Origin of Blackdamp,” by Mr. J. Ivon Graham, chief chemist of the Doncaster coal owners, and “The Flow of Air through Small Coal and other Broken Material,” by Mr. J. T. Storrow, chemist at Brodsworth Colliery (see p. 1198). A full report of the proceedings will appear in our next issue. Vacancies for certifying surgeons under the Factory and Workshop Acts at Mullingar, Dublin, and Cruden (Aber- deen) are announced.