47 6 l.EE POPULAR SCIEXCE MONTHLY. 



which was complained of as simply uninhabitable by reason of the 

 draughts that invaded it from all sides. A piece of iron pipe, with 

 the lower end protruded through the outer wall, the middle brought 

 through the fire, and the upper end open to the room, stopped all 

 cause for complaint. The reason for this is so obvious that it seems 

 hardly credible that a vast majority of dwellers in houses are enduring 

 continual torture for want of this pipe or some equivalent simple ap- 

 pliance. One looks in vain along the walls of our streets for any signs 

 of air-bricks or other inlets of air, and, with closed doors and plate- 

 glass windows, one wonders where the air comes from to feed the fires 

 within. There are but few available sources, which are these : 1. The 

 joints of the window-frames and chinks round doors, through which 

 cold blasts whistle as they are sucked in, so that these are pasted up, 

 and as far as possible this means of supply intercepted. 2. Unused 

 flues of other rooms down which air pours mixed with smoke ; and 3. 

 The soil and waste pipes, the water in the taps of which cannot hinder 

 the precious element from coming even by such undesirable channels, 

 in obedience to the powerful suction of the several fires in the house. 

 These failing, there are positively no other sources. Then, fortunately, 

 the fires begin to smoke, and doors and windows are perforce opened 

 to abate that by far the smallest and least dangerous nuisance of the 

 whole. 



The remedy for this is to provide a sufficiently ample supply of 

 pure, fresh air in such a manner that it may come in moderately warm, 

 and from such quarter that it be felt as a draught. There are several 

 means of doing this, each hotly maintained by its partisans to be the 

 only fit and proper one. The bottom, the centre, and the top of the 

 room, are each pointed out as being specially adapted for the purpose 

 bv those much-enduring laws of Xature, and the course of the currents 

 of air, demonstrated by flights of the most obedient and flexible ar- 

 rows. This certainly may be taken for granted : if openings be made 

 in any or all of the positions indicated, the laws of Xature will make a 

 beneficial use of them, but it will be capriciously, one moment as an 

 inlet and one as outlet, as the occasion may need. The fire being the 

 motive power of the currents, the direction that the air will take if it 

 can will be in a straight line to the fireplace, and, therefore, to obviate 

 disagreeable draughts, the air-inlets must not be placed so that cur- 

 rents thence must necessarily impinge upon the inmates of the room, 

 as in the case of the undesigned ones of the chinks round the doors 

 and windows. Again, they should not be so near and below the grate 

 as to rush direct to feed the fire, and thus, not only not aid to ventilate 

 the room, but absolutely take from the fire that valuable office. By 

 far the best mode,, in my opinion, is to introduce the air below tha 

 hearth, and carry it thence through warming-chambers at the back or 

 sides of the grate, and allow it to issue into the room above the fire- 

 place, or from the outer sides from the chimney-piece, so that it must 



