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(a) Great diminution of dust, since the ashes fall into a closed 

 ash-chamber. 



(6) Better warming of the room, with a diminution of about 

 one fourth in the quantity of coal used. 



(c) Diminished draft across the floor, from diminished roar up 

 the chimney when the fire is burning briskly. 



(d) Diminished production of soot. 



These are the principles which I have urged, and they are 

 open to every one to adopt. I do not speak of a further improve- 

 ment, as it is the subject of a patent, and is not open to every one 

 to copy. 



Having made sure of my fire, the next step would be to secure 

 admission of air to supply the fire, without making a draft or 

 introducing dirt. As far as I know this is best done by the 

 " Harding diff user," which admits air directly from the outside 

 and delivers it through a series of small jets near the ceiling. To 

 shut out the smuts the air passes through a canvas screen placed 

 diagonally in a flat tube, which leads up to the " diffuser " and 

 gives a filtering area about six times the sectional area of the 

 tube. This air is admitted into the room by a legitimate channel, 

 and is filtered. The " Harding diffuser " was once patented, but 

 the patent has lapsed. 



Having thus secured a supply of air for the chimney, we can 

 afford to deal with the windows, and make them air-tight, with- 

 out fear of the chimney smoking. Now I should like to see a 

 revolution in windows, at any rate, wherever we can be content 

 with panes of moderate size, and can have the heart to surrender 

 plate glass. 



Three things are required of a good window : 



1. That the outside of the window may be cleaned by a servant 

 standing inside the room, whereby the risk and expense of clean- 

 ing from without are avoided. 



2. That it shall exclude wind and dirt, even under the stress of 

 a gale. 



3. That the air of the room, especially in frosty weather, shall 

 not be itself so chilled by contact with the large surface of glass 

 as to cause induced cold currents, which have not even the merit 

 of being air freshly introduced. 



To attain these points, the sash window must be abandoned. 

 The window must be so divided that one half vertically, or in a 

 large window one third, may open inward on hinges, the other 

 half or two thirds being fixed, and therefore wind-tight ; the 

 breadth of each division to be such that a servant's arm can reach 

 out and clean the outer side of the fixed window as she stands 

 inside the room. In the case of three divisions the fixed windows 

 would be to the right and left of the hinged window. The hinged 



