doors from assisting in the removal of the upper stratum of vitiated 

 air, for the strong up-draught of the chimney causes these openings 

 to be fully occupied by an inflowing current ot cold air, which at 

 once descends, and then proceeds, as before stated, to the chimney. 

 If the leakage is insufficient to supply the necessary amount of chil- 

 blain-making and bronchitis-producing draught, it has to enter by 

 way of the chimney-pot in the form of occasional spasms of down- 

 draught, accompanied by gusts of choking and blackening smoke. It 

 is a fact not generally known, that smoky chimneys are especial 

 English institutions, one of the peculiar manifestations of our very 

 superior domestic comfortableness. 



It is true that, in some of our rooms, an Arnott's ventilator opens 

 into the upper part of the chimney, but this was intended by Dr. 

 Arnott as an adjunct to his modification of the German stove, and 

 such ventilator can only act efficiently where a stove is used. The 

 pressure required to fairly open it can only be regularly obtained 

 when the chimney is closed below, or its lower opening is limited to 

 that of a stove-pipe. 



The mention of a German stove has upon an English fire-worship- 

 per a similar effect to the sight of water upon a mad dog. Again and 

 again, when I have spoken of the necessity of reforming our fire- 

 places, the first reply elicited has been, " What, would you have ns 

 use German stoves ?" In every case where I have inquired of the 

 exclaimer, " Y/hat sort of thing is a German stove ?" the answer has 

 proved that the exclamation was but a manifestation of blind preju- 

 dice based upon total ignorance. These people who are so much 

 shocked at the notion of introducing " German stoves" have no idea 

 of the construction of the stoves which deservedly bear this title. 

 Their notion of a German stove is one of those wretched iron boxes 

 of purely English invention known to ironmongers as " shop stoves. ' ' 

 These things get red hot, their red-hot surface frizzles the dust parti- 

 cles that float in the atmosphere and perfume the apartment accord- 

 ingly. This, however disagreeable, is not very mischievous, perhaps 

 the reverse, as many of these dust particles, which are revealed by a 

 sunbeam, are composed of organic matter which, as Dr. Tyndall 

 argues, may be carriers of infection. If we must inhale such things, 

 it is better that we should breathe them cooked than take them raw. 



The true cause of the headaches and other mischief which such 

 stoves unquestionably induce is very little understood in this coun- 

 try. It has been falsely attributed to over-drying of the atmosphere, 

 and accordingly evaporating pans and other contrivances have been 

 attached to such stoves, but with little or no advantage. Other ex- 

 planations are given, but the true one is that iron when red hot is per- 

 meable by carbonic oxide. This was proved by the researches of Pro- 

 fessor Graham, who showed that this gas not only can pass through 

 red-hot iron with singular facility, but actually does so whenever 

 there is atmospheric air on one side and cabonic oxide on the other. 



For the benefit of my non-chemical readers, I may explain that 

 when any of our ordinary fuel is burned there are two products of 

 carbon combustion, one the result of complete combustion, the other 

 of semi-combustion carbonic acid and carbonic oxide the former, 

 though suffocating when breathed alone or in large proportion, is 

 not otherwise poisonous, and has no disagreeable odor ; it is in fact 

 rather agreeable in small quantities, being the material of champagne 



