1886.] on the Principles of Domestic Fireplace Construction. 339 



Mainly for two reasons : one, that there are priuciijles which a medical 

 man may work out without reproach, as tending to contribute to the 

 happiness, the comfort, and the health of mankind; the other, that 

 when principles have to be insisted upon, and to be made a subject of 

 public instruction, they can be urged with more effect by those who 

 are hampered by no relations to any patents, and have no pecuniary 

 interest in the success or failure of the ajjj^lication of the jDrinciples 

 in question. On this point we have a good example in Count Eumford, 

 who says in a note : — " The public in general and particularly those 

 tradesmen and manufacturers whom it may concern, are requested to 

 observe, that, as the author does not intend to take out any patent for 

 any invention of his which may be of public utility, all persons are at 

 full liberty to imitate them, and vend them for their own emolument, 

 when, and where, and in any way they may think proper." (III. 527.) 



Three evils result from the prevalence of bad principles in con- 

 struction : — 1. Waste of fuel and loss of heat. 2. Excessive production 

 of soot and smoke. 3. Large addition to ashj^it refuse by cinders, 

 which are really unburnt, and therefore wasted fuel. These are 

 matters of national concern, and it has been the main object of my 

 labours on this question during the last four years to endeavour to 

 convince the public that it is the interest no less than the duty of 

 every householder, to burn his fuel on correct principles, and to do 

 his part towards the diminution of these evils. 



On the first point, " Waste of fuel and heat," let us listen to 

 Eumford, whose words areas true to-day as when written eighty years 

 ago. " Though it is generally acknowledged that there is a great 

 waste of fuel in all countries, arising from ignorance and carelessness 

 in the management of fire, yet few — very few, I believe— are aware of 

 the real amount of this w\aste." (IV. 5.) " From the result of all 

 my inquiries upon this subject, I have been led to conclude that not 

 less than seven-eightlis of the heat generated, or which ivith proper 

 management might he generated, from the fuel actually consumed, is 

 carried up into the atmosphere with the smoke, and totally lost." 

 (IV. 6.) " And with regard to the economy of fuel, it has this in 

 particular to recommend it, that whatever is saved by an individual is 

 at the same time a positive saving to the whole community." (IV. 4.) 



Heat is wasted in three ways — either by combustion under the 

 impulse of strong draught, which means rapid escape of heat up the 

 chimney ; or by imperfect combustion of the gases which are generated 

 during the burning of the coals ; or by escape of heat through the iron 

 sides and back into the space between the range and the brickwork, 

 and so into the chimney. The greatest offenders are the ordinary 

 register grates. Iron all over, back, and sides, and roof, they are 

 usually set in a chamber open above to the chimney, and imperfectly 

 filled in, or not filled in at all, with brickwork. The heat escapes 

 through the iron to this chamber, and thence is lost. Another fault 

 is that the " register opening," in other words the " throat of the 

 chimney," being immediately above the coal, submits the burning fuel 



