NATURE 



[May 7, 1896 



Mr. Richards, and the only cure for the evils he emimeralcs is 

 to improve the inlellit;enceand the stalusof the working classes. 

 It is with regret that Englishmen too often see continental 

 employers superior to those of this country in regard to the 

 thoughtful care bestowed upon their workpeople. In some 

 cases it is true, care of the workman is forced upon the manu- 

 facturer by legislation, but in a great many instances the 

 continental iron and steel maker has recognised the wisdom of 

 treating his workpeople liberally. Doubtless in England we 

 may find many large-minded employers who, either from self- 

 interest or from motives of a higher character, pay much atten- 

 tion to the well-being of their workmen, but too often the 

 "hands" are looked on as simply an extension of the plant, 

 their sole function being to give the maximum of labour on the 

 minimum of outlay. It is hardly to be wondered at, under 

 these circumstances, that self-seeking persons obtain the ear of 

 the working man in this country, and so often advise them to 

 their own detriment and that of the nation at large. 



Mr. Windsor Richards concluded his address with some 

 rernarks on technical education. Referring to the want of 

 intelligence on the part of operatives he said, "yet the favourite 

 remedy of this state of things is, in many minds, to si^read 

 technical education all over the country ; whereas if the results 

 they desired unhappily be attained, the last state of the trade 

 would be worse than the first, for we should have no hewers of 

 coal, nor makers of steel." "Technical education" is so un- 

 certain a quantity that it is not easy to arrive at what Mr. 

 Windsor Richards exactly meant by his expression. We think, 

 however, that his words are likely to be misleading if not 

 mischievous. The most hopeful solution of the labour problem, 

 in fact the only solution, is higher intelligence on the part of 

 the workman, and there is no better way of fostering this 

 intelligence than by giving operatives such knowledge as will 

 enable them to appreciate the processes in which they are 

 engaged. Experience proves that a man does not become less 

 efiicient as a labourer, even as a hewer of coal and a maker of 

 steel, because he is educated, although frequently he may, by 

 virtue of his education, rise above these positions. We must, 

 however, leave Mr. Richards' address, and turn to the other 

 parts of the proceedings. 



At the last meeting of this Institution, a paper by Mr. W. H. 

 Patchell, on " Steam Superheating" was read, the discussion on 

 which was adjourned until the present meeting. Mr. Patchell's 

 paper referred to various designs of superheater, the principal 

 one treated upon being that of McPhail and Simpson. In this 

 apparatus steam is taken from the boiler and passed to a super- 

 heater which utilises the waste gases from the furnace. In this 

 way the steam acquires a certain amount of superheat. It is 

 then taken back to the boiler, and circulates in the water space 

 of the latter by means of an internal pipe. After this it passes 

 to the engine. The object of the invention is to obtain 

 thoroughly dry steam without the risk of it being highly super- 

 heated, and thus cutting cylinder faces, or leading to defects 

 which have been experienced in time past in using steam above 

 the temperature normal to the pressure. It will be seen, of 

 course, that this superheater, so called, is not necessarily a 

 superheater at all ; it may be, or may not be, the result 

 depending on the quantity of heat imparted to the steam by the 

 waste gases, and to the length of time the steam is subjected to 

 the influence of the water in the boiler by means of the internal 

 pipe. Supposing the steam be superheated several degrees and 

 then returned to the boiler, it will be subjected to the influence 

 of water at a lesser temperature than itself, for the water in the 

 boiler is practically at the temperature of saturated steam due to 

 the boiler pressure. The superheated steam may be reduced to 

 that temperature, but will not fall below it. I'ractically, we 

 believe, in an in.stallation with a Mcl'hail superheater, as usually 

 designed, the steam finally emerges from the internal pipe at a 

 temperature above that due to its pressure, but generally to a 

 small extent. It will, of course, be dry steam on finally 

 emerging from the internal pipe ; though possibly, in some 

 cases, surface radiation in the steam pipe between the boiler ami 

 the engine may deprive the steam of its superheat. It is further 

 to be noted that the heat which the superheated steam 

 parts with, to the water in the boiler, is not lost, but goes to aid 

 evaporation. If the degree of superheat of the steam as t passes 

 into the engine cylinder be small, .some of the steam will be 

 almost immediately liquefied by the usual process of extraction 

 of heat incidental to the working of any steam engine. If the 

 heat used for superheating be wholly waste heat, there will of 



NO. 1384, VOL. 54] 



course be a gain due to the adoption of the apparatus ; but 

 against this must be put the first cost of the superheater. In 

 any case it is an advantage to get dry steam, and the Mcl'hail 

 device must be credited with this. 



The principal contribution to the discussion was made by Prof. 

 W. C. Unwin, who claimed that Him should be credited with 

 the practical introduction of the use of superheated steam. In 

 Alsace he said su])erheaters are generally in use, and are found 

 to be of great practical value. If the apparatus were intelligently 

 designed, it was possible to use superheated steam without any 

 of the dangers and troubles of which so much had been heard. 

 A few years ago superheaters were largely fitted to a large 

 number of steamships in the form of the well-known steam 

 chimney, as doubtless the majority of our readers are aware. 

 The advent of higher pressures, and consequent higher tem- 

 peratures, however, brought difficulties. When steam of 30 to 

 60 lb. pressure was used, it was possible to increase the 

 temperature of steam above that normal to the pressure, without 

 introducing much complication, but when temperatures rose 

 much above those mentioned, as they speedily did with the 

 advance in boiler practice, superheating became a more serious 

 matter. Improvements in the packing of glands, and the intro- 

 duction of mineral lubricants, now enabled still higher tempera- 

 tures of steam to be used without danger. It may be as Prof. 

 Unwin says, that we can take useful example from the Alsatian 

 practice, and thus another era of superheating has arisen. The 

 introduction of the water tube-boiler also may supply an incentive 

 to marine engineers in this direction. The limited water and 

 steam space with this type of generator make it often difficult 

 to get dry steam, so that a superheater would fill a useful place. 

 Another point to be observed is, that if superheating of steain 

 be used, steam jacketing is not necessary, or at any rate not so 

 necessary as when non-superheated steam, often containing a 

 considerable quantity of water, is passed to the engine. Perhaps 

 when the paper on steam jackets by Messrs. Hudson and Donkin 

 is read, we may get further light on this subject, and it is to be 

 hoped ample time will be given for its discussion. 



Mr. MacCarthy's paper on " Electric Welding of Steam 

 Pipes " was a valuable and interesting contribution. Higher 

 steam pressures have brought trouble to tlje marine coppersmith. 

 The old brazed copper pipes have been found, by sad experience, 

 to be dangerous fittings, several lives having been lost by their 

 failure. .Steel pipes have been accordingly substituted where 

 high pressures are used ; and so far as the pipes themselves are 

 concerned, there is not much difficulty in producing a trust- 

 worthy article. The longitudinal welds of a lap-welded pipe 

 are made either by rolls or by the gas-welding system with a 

 hammer, in a thoroughly satisfactory manner, and experience 

 has shown how flanged junctions can be made. It is where 

 joints, such as elbows, T-pieces, &c. , are required that the 

 difficulty arises, and it is here that electric welding has come to 

 the help of the marine engineer. On the table of the theatre 

 Mr. MacCarthy exhibited several very fine specimens of steam 

 fittings of the kind referred to, a four-way branch being a notable 

 example. These were all made by the Benardos systein of arc 

 welding. Flanges are also welded to the length of pipe in the 

 same manner : the method of working was described by the 

 author as follows ; — 



" Ordinary low-tension continuous-current lighting dynamos 

 are used ; to the terminals of these a battery of Benardos 

 accumulators is connected, into which the current flows con- 

 tinuously. When the welding circuit is closed, the current 

 flows from the dynamos and accumulators ; and large resist- 

 ances are used when necessary. In this way a large discharge is 

 obtained, equal to about twice the capacity of the dynamos, and 

 the load factor of the apparatus is high. For some purposes it is 

 possible to work without accumul.-itors ; but when this is done, 

 the efficiency of the apparatus is not so high, because during 

 part of the working period no current whatever is passing, and 

 the machinery is running light." 



For attaching the flanges to the pipes, tlie following method 

 is adopted : — 



"The flange is stamped out under the steam hammer in such 

 a way that a V-shaped groove is left on the inside edge, extend- 

 ing about three-fourths through the thickness of the metal. The 

 flange is next shrunk upon the tube, with its flat face outwards 

 or at the end of the tube, and is carefully set in the exact position 

 required. The welding consists in laying small pieces of steel 

 in the V-shaped grove, and welding them in one by one by means 

 of the electric .irc, the welds being freely hammered between 



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