TRANSACTIONS OF THE SECTIONS. 237 



engines of railways, wliicli are under the especial charge of educated liieclianical 

 engineers, who carefully watch and tabulate all their results, and who have funds 

 at their disposal for the purchase and maintenance of good engines — that they 

 referred to the recent improvement in marine engines, which engines, being as a 

 whole in the hands either of powerful companies or of large capitalists, enjoy the 

 advantages of due outlay and of proper superintendence — and that they referred to 

 the prize engines and to the better competitive engines of the portable class, while 

 admitting the existence of a large number of such engines which were most wasteful 

 of fuel. But there remains the great class of fixed engines used for driving manu- 

 factories, which engines are, as a rule, of the most disgraceful and scandalous 

 character. In the first place, enormous numbers of them are non-condensing 

 engines : as an excuse for this it is in many instances alleged that water is scarce 

 and that there is not, therefore, the means of providing condensation. To meet 

 such excuses it should be remembered there are appliances well known to scientific 

 engineers (at all events that have been in use for many years) by which conden- 

 sation can be effected with no more water than is required for the feed of a high- 

 pressure engine. I allude to the ordinary cooling ponds for injection-water, and 

 to the surface-evaporation condenser. In every instance these may be employed ; 

 and thus, in lieu of sending steam into the atmosphere at a pound or two above 

 atmospheric pressure, that steam might be condensed, and a pressure of 12 or 

 13 lbs. additional throughout the whole stroke of the piston miglit be obtained ; 

 moreover the interior of the boiler would be kept clean, and thus its surfiice would 

 be in the best state for transmitting heat. 



But passing by this question of the repugnance to the use of condensing engines, 

 and admitting, for the sake of argument, that non-condensing engines may bo 

 allowed, what does one ordinarily find as a type of the non-condensing engine ? 

 One finds the cylinder with a cubic capacity far too great for the work required ; 

 where steam is used throughout the stroke, one finds that this capacity is not 

 utilized as it might be by the employment of high-pressure steam and considerable 

 expansion, and that while the steam, even in the boiler, is probably at only 40 lbs. 

 above atmosphere, the governor is flying out nearly to the full width, the throttle- 

 valve is all but closed, and there is a continuous " wire drawing " of the steam, so 

 that its average pressure throughout the stroke of the cylinder is only some 15 or 

 20 lbs. above atmosphere. Now when one recollects that it requires one portion 

 of coal to get steam up to atmospheric pressure, and that this portion may be 

 looked upon as practically constant, whatever pressure of steam above atmosphere 

 may afterwards be attained, and that if, therefore, steam at 15 lbs. above atmosphere 

 be used, half of all the fuel is lost, while if at 30 lbs. above atmosphere, 5 only is 

 lost, and if at 120 lbs. above atmosphere, J- only will be lost in getting up steam to 

 atmospheric pressure, one can imderstand how essential it is that in non-condensing 

 engines the steam should be used at a really high pressure ; and yet, as I have said, 

 I believe that if the large number of 10- or 20-horse horizontal non-condensing 

 engines employed by manufacturers throughout the kingdom were examined, and 

 indicator diagrams were taken, it would be found that their pressure upon the 



{listens did not average much more than 20 lbs. above atmosphere : and it is a 

 amentable fact that many makers of steam-engines — men who cannot be properly 

 called engineers ; men who are mere manufiictm-ers, not knowing the principles of 

 the art they follow — will boast that their engine is doing very well; it drives the 

 wliole of Mr. So-and-so's work and does not require more than 30 lbs. steam in the 

 boiler, not understanding that if they would raise that steam to 120 lbs., and then 

 work it uon-expansively in a small cylinder, they would thereby be obtaining a 

 great economy, and if they would work it expansively in a large cj'linder, that 

 cylinder being properly steam -jaclieted, they would obtain a still greater economy. 

 I have now laid before you some of the points in which the boilers and engines 

 of the present day are below the standard to which engineering science has already 

 reached, and in which, therefore, there is known opportunity for immediate 

 improvement. 



1 think there is so little reliable information as to the total horse-power at work 

 in the United Kingdom (as is evidenced by the fact that very recently the number 

 of boilers has been estimated before a Parliamentarv Committee as low as 50,000, 

 1872. ■ 17 



