236 THE POPULAR SCIENCE MONTHLY. 



away until they fall through the grid as a fine powder. This allows 

 the fire to burn clearly all day long almost without poking. When 

 the fire is low, and new coal is added, the reserve of heat in the hot 

 chamber is such that the addition of cold fresh fuel does not tempora- 

 rily quench the embers, and the fire is very quickly in a blaze after 

 being: mended. 



Having made the discovery by the observation of a grate supplied 

 to me with an " Economizer," the value of which, I suspect, was hard- 

 ly appreciated by the makers, I applied " Economizers " one by one to 

 all my grates, kitchen included. The result surpassed my expecta- 

 tions. There was a saving of at least a fourth of my coal. The ex- 

 perience of many friends, who, at my advice, adopted the system, con- 

 firmed my own results. It was, therefore, clear to me that I was 

 bound to make widely known a discovery which was fraught with 

 such benefit to myself, and was likely to prove a great boon to the 

 public. 



My chief aim hitherto has been to persuade the public to apply 

 the " Economizer " to existing fireplaces. After steady exertions for 

 four years, some impression has been made on the inertia of the pub- 

 lic, and extensive trials of the " Economizer " are taking place in many 

 parts of the country. To-day, however, my aims are more complete. 

 It is my wish to advocate not one principle alone, although that is the 

 cardinal one, but to urge all the best principles which enter into the 

 construction of a really effective fireplace, and to induce those whom 

 it may concern to replace bad by an entirely new construction, right 

 in every point. 



The rules of construction which I shall lay down have been arrived 

 at entirely by my own observation of what appeared to be the best 

 points in various fireplaces. It was, therefore, no less a satisfaction 

 to me than a surprise to discover, on reading Rumford's work in prepa- 

 ration for this lecture, that nothing which I have to advocate is new, 

 but that every principle, and the " Economizer " is hardly an excep- 

 tion, was advocated no less enthusiastically by him at the very com- 

 mencement of this century. 



Having considered the principles that should guide us, we are now 

 prepared to lay down strict rules which should be acted upon in the 

 construction of fireplaces. I trust that what I have said has so far 

 commended itself to your judgment that the fourteen rules here drawn 

 up will command your hearty assent, and in due time will win their 

 way into the confidence of our architects, our builders, and the public : 



Rule I. "As little iron as possible." The only parts of a fire- 

 place that are necessarily made of iron are the grid on which the coal 

 rests, and the bars in front. The " Economizer," though usually made 

 of iron, from convenience in construction, might be of earthenware, 

 and so would be more perfectly in harmony with this rule. On this 

 point Rumford speaks most emphatically : " Those (grates) whose 



