lesson, as well as a philosophical example. The best of all 

 smoke-abatement machines is an intelligent and conscientious 

 stoker, and every contrivance for smoke abatement must, in 

 order to be efficient, either be fed by such a stoker or provided 

 with some automatic arrangement by which the apparatus itself 

 does the work of such a stoker by supplying the fresh fuel 

 just when and where it is wanted. 



Cornish experience is very instructive in his respect. The 

 engines that pump the water from the mines do a definitely 

 measureable amount of work, and are made to register this. 

 The stoker is a skilled workman, and prizes are given to those 

 who obtain the largest amount of " duty" from given engines 

 per ton of coal consumed. Instead of pitching his coal in any- 

 how, cramming his firehole, and then sitting down to sleep or 

 smoke in company with his chimney, the Cornish, or other 

 good fireman, feeds little and often, and deftly sprinkles the 

 contents of his shovel just where the fire is the brightest and 

 the hottest, and the bars are the least thickly covered. The 

 result is remarkable. A colliery proprietor of South Stafford- 

 shire was visiting Cornwall, and went with a friend to see his 

 works. On approaching the engine-house and seeing a white- 

 washed shaft with no smoke issuing from its mouth, he 

 .expressed his disappointment at finding that the engine was 

 not at work. To all who have been accustomed to the " Black 

 Country," where coal is so shamefully wasted because it is 

 cheap, the tall clean whitewashed shafts of Cornwall, all so 

 smokebss, present quite an astonishing appearance. 



This is not a result of " smoke-consuming" apparatus, but 

 mainly of careful firing. It was in the first place promoted by 

 the high price of coal due to the cost of carriage before the 

 Cornish railways were constructed, and it brought about a 

 curious result. Horse-power for horse-power, the cost of fuel 

 for working Cornish pumping engines has been brought below 

 that of pumping engines in the places where the price of coal 

 per ton was less than one half. Another coal famine, that 

 should raise the 'price of coal in London to 60s. per ton, and 

 keep it there for two or three years, would effect more smoke 

 abatement than we can hope to result from the present and 

 many future South Kensington efforts. I need scarcely dwell 

 upon the necessity for a due supply of air. This is well under- 

 s!o)d by everybody. An over-supply of air does mischief, by 

 carrying away wastefully a proportionate quantity of heat. 

 The waste due to this is sometimes very serious. 



