DOMESTIC FIREPLACE CONSTRUCTION'. 231 



have lain dormant, lingering here and there, chiefly in old-fashioned 

 houses, and almost forgotten. 



Again, why should a layman, whose profession lies outside that of 

 the architect, the builder, and the manufacturer, take upon himself to 

 teach principles that are to guide other professions than his own ? 

 Mainly for two reasons : one, that there are principles which a medi- 

 cal 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 application of the principles in 

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

 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." 



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

 struction : 1. Waste of fuel and loss of heat. 2. Excessive produc- 

 tion of soot and smoke. 3. Large addition to ash-pit refuse by cinders, 

 which are really unburned, and therefore wasted fuel. These are mat- 

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

 on this question during the last four years to endeavor to convince 

 the public that it is the interest no less than the duty of every house- 

 holder to burn his fuel on correct principles, and to do his part toward 

 the diminution of these evils. 



On the first point, " waste of fuel and heat," let us listen to Rum- 

 ford, whose words are as 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 waste. . . . From the result of all my inquiries 

 upon this subject, I have been led to conclude that not less than seven 

 eighths of the heat generated, or which with proper management 

 might be generated, from the fuel actually consumed, is carried up into 

 the atmosphere with the smoke, and totally lost. . . . 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." 



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 gener- 

 ated 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 



