ICE - Institution of Civil Engineers - Virtual Library

42 DISCUSSION ON STEAM-ENGINE ECONOMY. [fiIiUUteS Of nrr. Davey. determined that the standard of efficiency for a perfectsteamengine, having a non-conducting cylinder, was adiabatic expansion. The steam-engine cylinder not was non-conducting, but being made of cast-iron, condensation i n it was an evil, whether it arose from adiabatic expansion or from other causes. It had been the endeavour of engineers since thetime of Wattto minimise the evil effects of cylinder-condensation by imparting ; additional heat to the working steam and it would be found that the highest economy would be secured by altogether preventing cylinder-condensation: that could only be effected byadopting some method bywhichthesteammight be keptdryandthe above theadiabatic line...

THE INSTITUTION OF CIVIL ENGINEERS. IV. SESSION 1894-95.-PART SECT. I.-MINUTES O F PROCEEDINGS. 19 March, 1895. Sir BENJAMIN BAKER, E.C.M.G., Vice-President, in the Chair. (Paper No. 2854.) " Stem-Engine Economy : Condensing-Engines." By HESRY DAVEY, Inst. C.E. M. THE principles which have governed the development of the steamengine as regards economy of steam were well understood in the time of James Watt, who showed that gain might be expected to result from increased expansion, and invented some ingenious devices for securing that result...

Proceedings.] DISCUSSION ON STEAM-ENGINE ECONOMY. 23 Discussion. Sir BENJAMIN BAKER, E.C.M.G., Vice-President, said there were Sir Benjamin many works in the field of investigation covered by the Paper, buttherewashardlyanyinvestigatorentitledto speak with on greater authority the subject, on the basis of practical experience, than the Author. He had, therefore, great pleasure in asking the of thanks for his members to accord him a veryheartyvote valuable Paper. Mr. HENRY DAVEY wished to be clearly understood that when Mr. Davey...

1.57 Ibs. perhorse power per hour; whereas in anexperiment at Oldford, the quantity was 4.82 lbs. ndtwithstanding the additional friction in the former case of the mining engine. The consumption is stated by Mr. Farey in his Treatise on the Steam Engine, for a double engine (Boulton and Watt) at 10+ Ibs. per horse power per hour. At the end of the paper are two Tables, the one shewing the gradual improvement of the steam engineduring 66 years, andthe other the average duty of engines in Cornwall for 1S35 and 1836...

80 CORRESPONDENCEPETROLEUM-ENGINES. ON [Minutes Of Correspondence. Mr.~ G. W. H. BROGDENcommunicated ~ d ~ ~ . some facts in connection with the working of a petroleum-engine at Bwllfa Dare Colliery, Aberdare. It was used to drive by gearing a three-throw pump, with barrels 6 inches in diameter and 14 inches stroke, pumping up some dip workings. The engine was of the Priestman type, 8 nominal HP., 10-inchcylinder,15-inchstroke,making 165 to 170 revolutionsperminutewhenpumping. It was startedin June, 1889, an& had been running continuously...

48 DISCUSSION ON PETROLEUN-ENGINES. [Minutes of Discussion. &h-B e r k l ~ . Mr. GEORGE BERKLEY, President,saidhewassure it wouldbe the desire of the members to pass acordial vote of thanks to Professor Unwin for his interesting Paper, which hehoped would leadto a useful discussion. He also statedthatthe following telegram had been received from Lord Kelvin :-`` Wish could be present to-night, Civil Engineers, to say how much pleased I am to find Priestman's engine now a practical success, having investigated it and formed very favourable opinion of it four years ago when i n experimental stage...

Proceedings.] DISCUSSION ON HICtH-SPEED ENGINER. 127 must be made, and it was of little use having one point excellent Mr.~ if the others were bad. To obtain good driving of dynamos by belt or rope, a very large margin of strength must be allowed, and excellent driving could be obtained only by direct coupling. hs. Correspondence. Professor M. F. GUTERMUTH found it difficult to judge the value E;:hGuterand practicability of the design of the Author's engine only by the description and the drawings...

HEATED AIK ENGINE. May 17, 1853. JOSEPH LOCKE, M.P., Vice-President, in the Chair, No. 897.--" On the Caloric Engine." By CHARLES MANBY, M. Inat, C.E. (Secretary.) AT meetings of the Socie`t6 d'Encouragement pour 1'Industrie Nationale, on the26thJanuary 1852, andatthe Acade`mie des Sciences, on the 2nd February of the same year, M.GalyCazalat entered upon an examination of Ericxson'6 caloric-engine, assuming it to be composed of the following parts :l...

HEATED AIR ENGINE. 591 Mr. C. MANBY, Secretary, read some quotations from a letter addressed by M. Regnault to Colonel Sabine, Treas. Royal Society, (datedApril 1853), in which he stated, thathe was aboutto publish, immediately, a series of elaborate experimental researches, on various subjects connected with the effects of heat on elastic fluids; the results of which would solve many questions long in dispute, and bymeans of which engineers might accurately calculate the effect of a given amount of fuel, in whatever way it was applied...