August 4, 1916. THE COLLIERY GUARDIAN. 209 steel ropes may press. In fact, in this case, and also that of the Conneaut plant, the real clamps are the ropes themselves, the parts termed clamps being merely pro- tective devices employed to secure car and ropes from damaging one another. It will be evident that bars extending clear across the car will have to be out of the way when the loaded ear enters the dumper, and also when the “empty” leaves. Furthermore, it is desir- able that whatever movements are made to comply with these requirements shall be automatic, and independent of the operator, i.e., they must not be power-operated movements. In the device used at Toledo, the ascend- ing and descending car or cradle brings the device into and out of action. The Toledo twin dumpers (fig. 5) have the short sec- tions of track laid on movable platforms, parallel motion bars being Used to shift the platform and loaded car up against the vertical side of the cradle by means of a slight incline. When the cradle, together with platform and loaded car, is lifted a little at the beginning, the platform shifts over at once. A bell crank is also employed here to return the platform and “ empty ” to the normal position in alignment with the track which serves the dumper. The counterweighting of the cradle is secured differ- ently at Toledo, the weight taken, which includes the cradle and part of the load, being managed in such a way as to put the drum of the winch on the rope. The system of counterweights relieves the winch, but the latter is always in control of operations. An idea of the size of the twin machines at Toledo may be gathered from the following items. Either dumper will accept cars up to 52 ft. in length, 13|ft. high, and ll|ft. wide. From centre to centre of main posts of the tower is 60 ft. The width of the base is 46 ft. and the height of the tower about 92 ft. The maximum lift of the oradle is about 34 ft. The apron may be varied in position through 30 vertical feet. The dumpers are steam operated, the steam coming from ’1 - \ >■ __ . I II 11 i - v ” I '. 11 f, " ’ W -V A ./■y' Fig. 5.—Twin Dumpers at Toledo (Ohio). an independent boiler plant. The face of the cradle against which the loaded car rests has been timbered, this being a requirement of the Master Car Builders’ Association. The method used by the builder of another car dumper at Toledo, the one built for the Cincinnati, Hamilton, and Dayton R.R. Company (fig. 3) for bringing the loaded car automatically over to the vertical side of the cradle differs rather markedly from the methods used by other makers. The same system has also been employed in the Sandusky and Cleveland dumpers. The loaded car stands on a wheeled plat- form. A link is secured by a pivot to the front side of the platform, whilst the other end of the link is pivoted to the upper arm of a three-armed lever, pivoted near the lower front edge of the cradle framework. There are two lower arms to the lever, one extending obliquely forward, the other obliquely to the rear. At the outer end of the forward arm is a wheel or roller running on a curved cam surface consisting of a short concave arc on a long radius. The -arm reaching obliquely towards the rear is shorter than either of the others, and to its outer end is secured the clamping chain which passes vertically upward. The car clamps are beams which extend across the car. top from one side to the other. The clamping chain which rises vertically from the shortest arm of the three- armed lever runs over the top of the hinged clamping beam, and is attached to the clamping counterweight rope which passes obliquely up and back. The rope is carried over a wheel or two, and hangs down at the rear of the tower. A clamping counterweight is attached to this end. As the loaded car comes on to the cradle, the clamp beam will be held obliquely above the car by the counterweight, As the cradle -is "hoisted, the clamping counterweight begins to rotate the three-armed lever, the movement being controlled by the roller as it runs on the cam surface. This movement causes the upper arm to move frontwards, and, consequently, pulls the wheeled platform and loaded car in the same direction. The car comes into contact with the underside of the hinged clamping beam. A pivot on the frame of the cradle engages a hook or socket, whereupon the turn- ing movement begins. The slipping of the car forward is prevented by the clamps, which are held against its top edges by their chains, ropes, and counterweights. On the return, the counterweights will, after a time, hold the hinged beams in their normal oblique posi- tions, the cradle settling further down. Push bars, extending down through the floor of the cradle, come into action as the cradle approaches its bottom position, in consequence of the reaction of their lower end against a fixed pad, and serve to force the clamping beams off the car as the cradle settles to rest. They also keep the clamps from engaging the top of the loaded car at the beginning of the lift until sufficient opportunity has been allowed the clamping counterweights, acting through the three-armed levers, to force the car over to the front vertical side of the cradle. The roller engages the cam surface, and is accordingly moved forward, the upper arm of the three-armed lever being consequently forced backward, with the result that the track on the wheeled platform is again brought into alignment with the approach track of the dumper. SULPHATE OF AMMONIA ASSOCIATION. The -second annual report of the Sulphate of Ammonia Association states that the association has extended the scope of its work in every direction, and has now come to be generally regarded as the representative and defender of manufacturers’ interests in all matters germane to the production of sulphate of ammonia. The Ministry of Munitions has constantly sought its assistance and advice upon general and technical ques- tions. Although the association was unable to prevent the Boards of Trade and Agriculture from enforcing a total prohibition of export during the spring months, thereby causing irreparable loss to the country and great inconvenience to manufacturers, the suggestions and estimates offered them regarding the method of issuing licences and the quantities required by home agricul- ture have predisposed those departments favourably towards making more businesslike arrangements for the coming season. The efforts to secure a limitation of prices for sulphuric acid met with better success, and are considered to have led the Ministry of Munitions to fix the maximum prices now in force. The activities of the selling branch have been con- siderably extended, the number of manufacturers who have entrusted the association with the entire sale of their sulphate has increased, and the quantity sold for other members has also increased, so that the tonnage disposed of during the year is very, considerably greater than the total sales last year. Apart from this, a large number of manufacturers who prefer still to retain sales in their own hands make a practice of consulting the association before selling. The volume of business transacted directly with consumers has also increased, among the contracts secured being one with the French Government for the supply of sulphate of ammonia for munitions. Weekly reports and lists of sales have been issued to members of the selling branch, and, in addition to this, the association has circulated valuable information con- cerning matters affecting the trade, with special refer- ence to the increase in production of nitrogen in Ger- many. The selling branch has continued to fulfil a- useful function, the increase in the tonnage contributing to this branch from new members amounting to 8,228 tons. The total tonnage contributing to this branch now exceeds last year's by over 10,000 tons. In the last report special attention was drawn to the question of quality. Allowing for -the difficulties experi- enced in obtaining the right qualities of sulphuric acid, the effect of the association’s pamphlets and suggestions is beginning to be felt, and the quality of sulphate pro- duced has improved on an average. There is still room for further improvement, however, and the association trusts that all members will make due preparation now so that as soon as conditions are again normal they will be able to produce 25 per cent, sulphate of ammonia in good mechanical condition. Special attention is also drawn to the desirability of employing strong bags of good outward appearance for home sales. Members have shown a growing disposition to seek the assistance of the association’s expert in the manu- facture of sulphate of ammonia, and Mr. Clark has devoted as much time to this work as his duties with the Royal-Naval Air Service allowed. The work of the selling branch has been intimately associated with that of the propaganda branch, and, as foreshadowed in last year’s report, greater attention has been devoted to commercial questions. In accordance with the decision of the propaganda committee, certain alterations are being carried out in the organisation of the outdoor staff, with the idea of increasing the effici- ency of the association as a distributing agency without interfering with its scientific activities. The efforts to interest corn and manure merchants in sulphate of ammonia have met with marked success, and the steps which have been taken to maintain uniform prices over large districts for a month and more at a time have undoubtedly greatly assisted sales. The fact that the prices charged to farmers and manure merchants have been on an average about 30s. per ton below the export selling value is sufficient reply to numerous critics in Parliament and elsewhere who have accused the asso- ciation of constituting a ring, whose sole object is the forcing up of prices. From the figures and estimates obtained, the associa- tion i-s able to report that the increase in the quantity of sulphate of ammonia used by home agriculture last season was over 10 per cent, in excess of the tonnage taken in previous years. Although this increase is not as large as could have been wished, the result is satis- factory when the innate conservatism of farmers, the exceptionally bad weather, the reduction in the acreage of green crops, and the scarcity of labour are taken into account. Although the actual increased quantity used is not very large, a larger number of individuals than ever before have used sulphate of ammonia, and it is confidently expected that this will form the basis for a large development in the future. In conformity with the alteration of policy decided by the committee, fewer manurial experiments have been carried out this season, and in future the intention is to make fewer experiments, but on larger areas, and with a view to solving particular problems. A large quantity of literature of all descriptions was distributed throughout the season, including brochures on “ The Market for Sulphate of Ammonia and its Future,” “ Does it Pay to Make 25 per cent. Ammonia?” “ Suggestions for the Manufacture of High Testing Sulphate of Ammonia,” “ The Manure Richest in Nitrogen,” “ Luxurious Growth,” and a large number of the Board of Agriculture’s leaflets advocating the use of sulphate of ammonia. With a view to facilitating the purchase of supplies by corn and manure merchants, classified lists of producers throughout the country were prepared, and met with a large demand. Propaganda work was also carried out in Scotland, Ireland, Spain, and Egypt. In view of the shortage of supplies of sulphate of ammonia in the counties of Cornwall, Devonshire, Somerset, and in a number of Welsh counties, the asso- ciation arranged to pay part of the railway carriage from neighbouring centres of production, and a considerable quantity of sulphate of ammonia was sold in this way at a price which did not interfere with the sales of local producers. The committee .regard the money spent in this way. as a good advertisement for sulphate of ammonia. The tonnage represented by subscriptions to the pro- paganda branch, viz., 325,447 tons, shows an increase of about 1,500 tons as compared with last year. To this must be added the production of several important manufacturers, who have decided to join the association as from July 1, 1916. The total tonnage of new mem- bers is 11,000 tons. Among the new members are the Bengal Iron and Steel Company Limited, the Metro- politan Gas Company of Melbourne, and Natal Ammo- nium Limited. According to revised estimates, the quantity of sul- phate of ammonia as such produced in the United Kingdom amounts to about 360,000 tons per annum, so that the Association is very nearly completely represen- tative of British production. It is with deep regret that the committee have to record the deaths of two of their colleagues—Mr. John Fyfe, of Young’s Paraffin Light and Mineral Oil Com- pany Limited, and Mr. W. J. D. Burnyeat, of the Cumberland Coal Owners’ Association. Mr. Fyfe had been an active member of the executive since the for- mation of the Sulphate of Ammonia Committee in 1897. Mr. Burnyeat joined the executive on the formation of the Selling Committee. An agreement has been reached in the coal mining dispute in Australia pending arbitration. Engineering Standards Coir.:.iittee.—At a special meeting of the main committee I Sir John Wolfe Barry, K.C.B., chairman) held on July 27 last, Mr. Charles le Mais-tre, A.M.Inst.C.E., M.Inst.E.E., who has been in charge of the work of the electrical section since 1903, was appointed secre- tary to the committee in succession to the late Mr. L. S. Robertson, M.Inst.C.E., who was lost with Lord Kitchener in the disaster to H.M.S.' “ Hampshire ” whilst on an important Government mission.