October 30, 1914 _______________________________________________________________________________________________________ THE COLLIERY GUARDIAN. 021 and limb is, however, so great in this class of work that the Department would be failing in its duty if it omitted to warn managers of the danger of employing an indivi- dual who has twice been proved guilty of gross negli- gence, and the only possible way of doing so is by endorsing the certificate. Employers might also reasonably consider that they had a moral, if not a legal, claim to be protected by the Department against persons holding certificates who are not entitled to be fully entrusted with the responsibilities attaching to such certificates. As hitherto, the majority of the wire rope tests carried out at the laboratory were the bi-yearly tests of ware ropes used for the raising and lowering of persons, as required by the Mines, Works and Machinery Regula- tions. A noteworthy feature in connection with these tests is the small variation between the actual breaking loads of the ropes as tested at the mechanical laboratory, and as declared by the makers and suppliers of the ropes. This is most probably due to the fact that, in a number of cases, new ropes are tested in the country of manufacture before being sent out to this country. The depreciation in the breaking load of wire ropes used in compound and incline shafts, due to wear and arrested vibration at the capel ends of the ropes, was exemplified under test in a number of cases. The following is an instance :— Rope of 8/6/1 construction, Lang’s lay; plough steel —128/134 tons steel (stress per sq. in.); breaking load (when put into use), 59’024 tons. After six months’ wear the breaking load—under test—w’as 35-85 tons, a reduction of 39’3 per cent.; seven days later a length of, approximately, 50 ft. was cut off the end of the rope and tested, the result being 41-62 tons, a reduction of 29-5 per cent.; 14 days later a further length of approximately 100 ft. was cut oft, and the test result was then 50-21 tons, or a reduction of 15 per cent, from the original breaking load of the rope. A feature to be noted in connection with the class of steel used in the manufacture of wire ropes is that a lower breaking stress per sq. in. is now employed, the average being approximately 120 tons (of 2,0001b.) per sq. in. A number of tests were made in the “ Vaughan- Epton ” fatigue testing machine. In one case a wire rope used for the raising and lowering of persons was found to develop broken wires to an alarming extent each day. When the individual wires composing this rope were tested in the fatigue testing machine, it was found that only 50 per cent, of these wares were able to withstand the continual bending and tensile stresses to which the rope was subjected when in use without undue .stretching, which accounted for the breaking of the indi- vidual wires. The ordinary methods of test (tension, bending, and torsion) showed no appreciable difference in the wire composing the rope. In another case, ropes of different makers working in contiguous compartments of a shaft varied considerably in their length of life, the daily work performed by each rope being practically the same. It was proved from fatigue tests of the wires from an unworn sample of each of these ropes that the difference in quality could have been initially established in the laboratory. (To be continued.) ____________________________ MINING AND OTHER NOTES. Messrs. Ronald Trist and Company Limited, of Coronation House, 4, Lloyds-avenue, E.C., advise us that they have retained the services, as manager of their machinery export department, of Mr. George A. Goodwin, M.I.C.E., past-president of the Society of Engineers. Mr. Goodwin’s department is prepared to act as a buying agency, inviting tenders on receipt of clients’ indents, placing orders, supervising the construction of work in the makers’ shops and carrying out tests, wherever possible, on completion. Alternatively, inspections alone will be undertaken. This department is also prepared to enter into an approved agreement to finance orders, subject to the usual references, and accept payment on terms as may be arranged. A presentation of a silver cigar box was made on Wednesday evening (October 21) by the directors and friends of the Coal Trade Benevolent Association, at a private dinner at the Holborn Restaurant, London, to Mr. H. C. Rolfe, the chairman of the directors. Mr. Gilbert Alder presided, and the presentation was made by Mr. G. W. Willcock. Messrs. Edward Bennis and Company Limited inform us that they have a number of lantern slides dealing with the development of mechanical stocking, elevating and con- veying apparatus, which they will be pleased to loan to any responsible engineer for lecture purposes. A list of the slides and particulars of their subject matter can be obtained on request. Applications for the loan of slides should be made well in advance of the lecture date, and should be addressed to the Publicity Department, 28, Vic- toria-street, S.W. The council of the British Electrical and Allied Manufacturers’ Association decided at the last meeting not to hold the usual annual dinner this session. The Manchester School of Technology possesses par- ticulars of more than 550 students who were in attendance at the college during the academic year 1913-14, and who are now serving in various branches of his Majesty’s forces. With a view to the completion of a roll of honour, which shall also include the names of past students engaged upon military service, the registrar will be glad to receive any information from such persons themselves or from their relatives or friends. The amount subscribed to the Sir William White Memorial Fund has now reached a total of nearly <£3,000, and it has been decided to devote the principal part of the fund to the establishment of a scholarship for research work in naval architecture, particulars of which will be announced in due course. Any further contributions will be gladly received by the secretary, Institution of Naval Architects, 5, Adelphi-terrace, W.C. ACCIDENTS FROM EXPLOSIVES IN 1913. The 38th annual report of his Majesty’s inspectors of explosives for the year 1913 has been issued by the Home Office. [Cd. 7650.] In the report for 1912 a hope was expressed that when the first rush of tests at Rotherham was over, more time would be available for inspection work, this being qualified, however, by a caution against taking too optimistic a view in this regard, and. the experience of the past year seemed to indicate that the warning was by no means out of place. Capt. Thomas, who was temporarily appointed to take Capt. Desborough’s place during the latter’s absence at Eskmeals, has been largely occupied in testing and preparing the specifications of safety lamps, and has had little time for inspection work, which has suffered accordingly. But in spite of this unavoidable decrease in the number of inspections, the work both of the inspectors and the clerical staff has become more and more strenuous, even when judged only by the volume of correspondence received and issued during the year, this alone showing an increase of 17 per cent, as compared with the year 1912, 29 per cent, as compared with 1911, and 83 per cent, as com- pared with 1897, when the last increase in the number of inspectors was sanctioned. In these circumstances, and having regard to the rapidly increasing importance of the petroleum industry, it is suggested that the day is not far distant when even the full services of four inspectors will be insufficient to carry on the work of the Department at the level which the inspectors have always sought to maintain. Work at Rotherham has been practically continuous during the year, and a large number of new explosives have been submitted to test. As stated in last year’s report, it was hoped at one time that the new “ Per- mitted List ” would be ready for issue on March 31, but owing to unavoidable delay this was not possible. In any event, however, it would have been necessary to allow a certain period during which both the old and new lists wTould be available, in order to enable mine managers to get accustomed to the new explosives, so that the postponement of the date of expiry of the old list until December 31 was not altogether unexpected. A further postponement was eventually made to March 15, 1914. The explosives on the new list are, as is only to be expected, somewhat less powerful than some of those on the old, but it is satisfactory to note that those more recently tested show, on an average, a marked increase in efficiency. The report of chemical advisers states that the total number of samples examined during the year amounts to 506. This, although larger than it has been for the last two years, is considerably smaller than it was in 1907, in which the number was the highest ever recorded. This drop in the number of samples examined is all the more noticeable as, previous to that date, there had been a fairly steady tendency to rise from year to year. There appear to be two reasons for this fall in numbers. First, that for the last few years con- siderably fewer samples have been received in connec- tion with the importation of explosives; secondly, that the enormous amount of work required at Rotherham during the last three years has unavoidably interfered somewhat with the number of samples taken by the inspectors. It is pointed out, however, that the amount of work necessitated by the samples received now is a great deal more than was required by the same number of samples in earlier years. There are two reasons for this : first, that a much greater proportion of the samples received are completely examined than used to be the case; secondly, that owing to the enormously increased complication in the composition of modern explosives —and this increase has been especially noticeable since the new testing station was opened—the average amount of work required for each analysis is at least twice, probably three times as much, as it was, say 10 years ago, and increases every year. It will thus be seen that, although the number of samples has diminished some- what, the amount of time occupied in their examintion has very seriously increased. The number of samples rejected is normal, although it may be worth while to point out that the number of samples rejected for exudation, to which special atten- tion was drawn in the report for 1912, is far less than it was in that year. The number of samples examined in connection with the testing station has, in conse- quence of the activity of the manufacturers in bring- ing forward explosives for the new test, been very much larger than usual, and, as the composition of most of the samples has been very complicated, this branch of the work alone has taken up a very considerable amount of time. A special investigation was carried out as to the exudation of carbonite. The number of accidents by fire or explosion of which the Department has had cognisance during the year was 498, causing, as far as is known, 66 deaths and injuring 485 persons. The total number of accidents shows an increase from 1912, viz., 498 against 456, and is above the average (425-3) for the past 10 years. The number of deaths from accidents is more than in 1912, viz., 66 against 35, and is more than the decennial average (55-1). The number of persons injured last year was 485, as against 429 in 1912, and is above the decennial average (430-7). Over 89 per cent, of the accidents causing death or personal injury occurred in the use of explosives and under -miscellaneous conditions to which the controlling provisions of the Act do not apply, and such accidents caused 48 out of the 66 deaths, and 427 out of the 485 cases of injury. This leaves a balance of 47 accidents- causing death or personal injury in manufacture, storage and conveyance, these being the conditions to which the Act does apply. By these accidents 18 persons, i.e.,. 13 more than in 1912, were killed, and 58, or 22 more than in 1912, were injured. The number of such acci- dents is 20 more than in 1912. Of the 95 accidents in manufacture, keeping, and conveyance, no less than 48 were unattended with personal injury, whilst of the 403 accidents in use, etc., only two came under notice which were free from personal injury. The following table shows the total number and nature of fatal accidents occurring in the use of the different explosives, and under miscellaneous circum- stances in 1913* Class of explosive. 1. Gunpowder... 2. Nit rate-mixture 3. Nitro-compound Div. 1 ... Div. 2 ... 4. Chlorate-mixtur Div. 2 ... 5. Fulminate ... 6. Ammunition: Div. 1 ... Div. 2 ... Div. 3 ... ... 7. Firework:— at 4 of liL- Nature ___ { . No. of explosive. acci. dent . Gunpowder ... 202 Bobbinite ..... 7 . Westf alite ..... 4 "Abbcite ....... 2 Arkite ......... 14 Blasting gelatine 2 Celtite _________ 1 Dominite _____ 1 Dynamite ..... 1 Excellite....... 1 Fracturite ..... 1 Gelatine dynamite or gelignite... 68 M n bel p<»wder. 9 Nobel polarite ... 1 Normanite..... 1 Permonite ..... 3 Rexite ________ 3 Rippite......... 8 Samsonite ..... 16 Stomonal....... 1 Stow-ite ....... 6 _Swalite......... 5 "Ammonal ..... 5 Am • onite ..... 5 Bellite No. 1 ... 2 Fortex......... 1 Kentite ....... 2 ^St. Helen’s pwdr. 1 i Cheddite....... 2 t Ste elite ....... 1 Railway fog signal 1 Safety cartridges 2 Filled shell.... 1 Detonators or elec- 20 trie detonators mts causing loss or bodily injury. No. of persons Kille '. Injured. 22 . .. 204 — 7 1 . 3 1 .. 2 1 . .. 16 - 4 1 : — — 1 — 1 — 1 i ; .. — u . .. 82’ i . 9 — 1 — 1 — 3 — 3 2 10 4 . .. 17 — 2 — 6 3 . 3 — 5 — 5 — 2 — 1 — 2 — 1 2 — 1 — — — 1 — 3 I — ... 26 Div. 1 ... - — ... — ... — tv o’ (Signal rockets ... — ... — ... — D1V-J ...1 Socket signals ... 1 ... — ... 1 Totals................ 401 ... 48 ... 427 With regard to accidents in keeping, the number was six, being three more than in 1912. One accident which deserves attention occurred in a store at West Shield Row Colliery, Stanley, Durham. The storekeeper was taking frozen cartridges of stow-ite out of miners’ tins when he dropped one about 3| ft. on to the wooden floor. The cartridge exploded, severely injuring the store- keeper, but fortunately the explosion was not communi- cated to the remainder of the explosive in the store. The number of accidents grouped under the heading of “ Use and miscellaneous ” is more than in 1912, being 403 against 348. By far the larger number of these accidents are connected with blasting. The number of persons killed by these accidents is more than last year, viz., 48, as compared with 30, and the number of persons injured is also more, 427, against 393 in 1912. The accidents are classified under the headings of the cause as follow :— No. of No. of p rsons Cause.* acci- f ' r dents. Killed Injured. Shot-firing— Prematures and failing to get away from shot-hole (22) 18 1 .. 23 Firing by electricity when persons are at the shot-hole (10) 15 2 13 Not taking proper cover (68) 101 8 / 95 Projected debris (19) 2 2* Hang-fires and returning too soon to the shot-hole (44) 46 7 .. 48 Tampering with miss - fired shots (18) ..... 17 — 24 Ramming or stemming the charge (36) 36 5 42 Sparks, flame, &c. (79) 97 9 .. . 102 Boring into unexploded charges (14) 18 3 .. 21 Striking unexploded charges in removing debris (18) 5 1 .. Preparing charges (6) 2 — 2 Lighting fuse before inserting charge (1) 2 — 2 Fumes (1) - — ... . Hot or unexploded residue left in borehole af ter *(socketing ” (10) 7 2 .. 8 Various (7) ... 12 5 .. 9 Miscellaneous:— Playing with detonators 9 — 11 Playing with other explosives ... 3 — 4 Sparks, &c., unconnected with shot-firing 1 —• 1 Breaking blasting cartridge 1 .7 i •’/ 1 Destroying explosive 1 — 1 Explosive in coal 2 — 6 Fishing with explosive 1 — 1 Putting explosive on fire 1 3 / — Testing cattle killer 1 — 1 Thawing 2 1 / 1 Filled shell 1 1 Signal rockets and socket signal .. 2 — 1 ■ II ■ " ■1——"1— Totals 403 ... 48 .. . 427 * The figures in brackets denote the average number of similar accidents during the previous five years. * Under this head are included all accidents which occurred in the use of explosives and immediately connected therewith; also accidents in thawing dynamite, and others arising from miscellaneous causes not within the prohibi- tions of the Act. In short, this group comprises all accidents occurring under circumstances not immediately controlled by the Act.