TRANSACTIONS OF SECTION G. 803 



■country and the Continent ; and this is a point that calls for special consideration, 

 because although centre-buffers are so unfamiliar in this country, they are really in 

 the majority, as regards the length of railways upon which they are used, which 

 include North America, great part of South America, Australia, and part of India. 



The double side-buffers of this country are intended to transmit the shocks of 

 buffing to the side sole-bars of the underframes ; but in practice, on account of the 

 frequent curves on the railways, the shocks of buffing are received mainly upon 

 one corner only of the frame, with a tendency to strain the frame ; with centre- 

 bufiers, however, the shock is always received at the same point of the frame, 

 whether on a straight line or a curve. Any steadying action to the carriage in 

 running derived from the contact of buffers at both sides, is also materially inter- 

 fered with by the difference in pressure of the two buffers when upon curves ; but 

 with centre-buffers the hold of the buffer-faces for steadying action is continuous 

 and independent of curves. A very important advantage in working is gained with 

 centre-buffers, in the open and safe access to the couplings that is afforded, thus 

 getting completely free from the obstruction of side-buffers which is so serious a 

 source of accident to the men in the present English system ; and this point is now 

 made of still greater importance by the extensive use of continuous brakes, which 

 require the coupling of brake air-pipes in the centre, in addition to the draw-bar 

 couplings. 



In the English carriage couplings there is not any provision against the tele- 

 scoping of the carriages in a collision, which is the great source of inj ury in train 

 collisions, the coupling being flexible vertically as well as horizontally ; but the 

 American carriage coupling most extensively used is rigid vertically, preventing 

 displacement beyond a limited range, and it forms a provision for preventing one 

 frame mounting upon the next one in a collision, and the consequent telescoping of 

 the carriage bodies ; this coupling has a strong metal bar projecting from the end 

 of each carriage frame under the next carriage, which must be broken away before 

 either carriage can mount. This coupling is automatic, and is worked by bumping 

 the carriages together ; the coupling jaws are wedged apart horizontally by the 

 striking together of the projecting tapered ends, and then engage together by 

 springing back to the central position. There is, however, no means of tightening 

 up this coupling beyond the original compression of the buffers in bumping up ; and 

 although the carriages are usually held very steady in running, it happens not 

 unfrequently, with the extra stretch of the draw-springs in a heavy train, that the 

 buffer-faces get slack or even separated, allowing a side oscillation of the carriages, 

 which cannot be checked, and which is a serious defect in this coupling. The 

 very severe bumping blow that is required with this coupling is also particularly 

 objectionable to the passengers. 



The American wagon couplings are made by a link with a drop-pin, the link 

 passiT> • through an opening in the centre of each buffer-head, and the link is long 

 enough to allow the required amount of slack between the buffers; the buffers 

 are made with a combined buffing- and draw-spring. The great defect in these 

 American couplings is that the carriage and the wagon couplings, instead of 

 being completely interchangeable, as in English practice, are so entirely different 

 that the coupling of a carriage to a wagon is only effected by an unsatisfactory 

 make-shift; the projecting end of the carriage coupling-bar has a slot and pin- 

 hole for attaching the wagon coupling link, but the only buffing provision then left 

 is the pointed end of the carriage coupling-bar striking against the curved wagon 

 buffer-face, the carriage buffer being at a different level above. 



The English screw-couplLng seems the most efRcient means of tightening up the 

 couplings of carriages, as it provides for giving an equally tight coupling with 

 variations in the length between the carriages ; but this efficiency only lasts complete 

 whilst the train is standing, and in running it is seriously impaired by the stretch- 

 ing of the draw-springs, which is often so great in the forward portion of a heavy 

 train as to leave the buffer-faces quite slack or separated. A perfect coupling 

 requires to be quite independent of the pull, and to retain its original tightness under 

 all circumstances ; and this is only practicable with a solid coupling having no draw- 

 spring. Now the present carriage draw-springs have really but little action in easing 



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