28S REPORTS ON THE STATE OF SCIENCE, ETC. 



The most frequent and serious cause of avoidable heat-wastage in current 

 boiler practice arises from the fact that unnecessarily large excesses of air 

 are usually drawn through the system owing to sheer neglect of some of the most 

 obvious ijrecautions. With good management it should be possible, by careful 

 damper regulation and maintaining a correct depth of fire, to burn completely 

 an average quality of steam coal with no greater excess of air than would 

 give about 12 per cent, of CO2 {without appreciable quantities of CO) in the 

 chimney gases ; but far too frequently as much as twice such minimum excess 

 of air is drawn through the system. It is not sufficiently realised how highly 

 important to fuel economy are the proper regulation of the draught by dampers, 

 the correct proportioning of grate area to the quantity and size of the coal burnt, 

 and the avoidance of inleakage of cool air into the boiler setting by keeping 

 the brickwork in good repair and well pointed, and efficiently caulking the joint 

 between the brickwork and boiler shell. Proper attention to such elementary 

 points would reduce the ' sensible heat ' lost in the chimney gases to 18 per 

 cent, of the total calorific power of the coal burnt, whereas neglect of them 

 often means twice such loss. 



Whilst the more general use of indicating and recording apparatus may be 

 recommended as the best automatic aids to good management, yet unless these 

 are supplemented by intelligence and watchfulness on the part of both stokers 

 and boiler-house superintendents they will not avail much or may be actually 

 misleading. The Committee, therefore, desires to impress upon both manufac- 

 turers and the public education authorities the need there is not only of better 

 boiler-house supervision but also of the better instruction and training of the 

 boiler-house personnel. It cannot be urged too often upon steam users that 

 considerable economies can be effected with existing plant and appliances, 

 provided that they are run under the skilled supervision of properly trained 

 men. In the case of large boiler installations it will usually pay to put them 

 under the control of a well-trained fuel technologist, and there are several 

 institutions in the country where such men are being scientifically as well as 

 practically trained. Local education authorities could effectively help fuel 

 economy by instituting in the various technical schools throughout the country 

 properly organised classes for the instruction of stokers and the lower grades 

 of boiler-house attendants. In addition to such classes, the institution in some 

 of the larger centres of more advanced and specialised lectures, with opportunities 

 for discussion, upon combustion, heat transmission, and boiler management 

 generally for boiler superintendents and engineers, would undoubtedly be of 

 great advantage. 



In connection with the production of electric power by Public Utility Under- 

 takings, the Committee would point out that the Electricity Commissioners could 

 render a great national service if, in their annual returns, they would publish 

 such financial and detailed technical data as are necessary to show tlie actual 

 fuel consumptions and total cost of production per unit of output in the various 

 individual power stations throughout the country. The present annual returns 

 are not sufficiently detailed for this purpose, and in particular do not show the 

 circumstances (such as load factor) under which the current is produced. It 

 would undoubtedly stimulate healthy competition, promote fuel economy, and 

 reduce costs if the individual power stations were required to furnish for 

 publication all the necessary technical data to enable fair comparisons to be 

 made. 



VII. Smoke Abatement- 



During the past year the Departmental Committee appointed by the Ministry 

 of Health 'to consider the present state of the law with regard to the pollution 

 of the air by smoke and other noxious vapours, and its administration, and to 

 advise what steps are necessary and practicable with a view to diminishing the 

 evils still arising from such pollution,' has issued its Final Report. After full 

 consideration of the matter, it was not thought practicable at present to propose 

 legislation dealing with smoke from private dwelling-houses, although it was 

 estimated that as much as 2^ million tons of potential fuel in the form of soot 

 escape annually into the atmosphere from domestic fire-places, as against only 

 500,000 tons from factory chimneys, which latter seems a very low figure. It 



