BY JAMES TOLSON, ESQ. 717 
which comes through the walls themselves. What this may 
amount to depends entirely upon the insulation of the 
building. In fact the whole stream of heat from the walls, 
as well as that from the radiant, is transferred by contact 
to the cold air. 
As in practice the results previously calculated are not 
always obtained, the cause must be looked for in the want 
of opportunity for the meat to give up the contained heat. 
Fig 6 shows at once how dehicrent is the wall area, the only 
place where the heat radiating from the meat can lodge, 
and also that the majority of the quarters hanging in the 
room are unable to part with their radiant heat to any 
extent (and how much more must this be the case when 
double the number of quarters are hung in the same space.) 
Consequently, the object to be aimed at is to crease the 
area of surface available for receiving the radiation, and 
which will also at the same time increase that to be brought 
in contact with the cold air. 
Proceeding now to increase the area of the recipient or 
absorbent, that is, to give a larger proportion of surface of 
some solid material which shall act as a medium of 
exchange between the radiant and the cold air, care must 
be taken that we do not interfere with the free circulation 
of the cold air. 
The following diagram (fig. 7, plate II.) will illustrate one 
method of doing this, and its simplicity and cheapness are 
points in favour of its adoption. 
The radiants are hung in the same manner as before, 
and between each is suspended a calico or canvas screen, 
or, in fact, a screen of any material. As the value of A, or 
the loss by contact of cold air is the same from the surface 
of all materials, a canvas screen will answer as well as 
anything else, and it has the advantage of portability. 
Hung, say, by hooks, at a distance of 12 inches from the 
ceiling, and reaching to within 18 inches of the floor, it 
would present a surface to each quarter, and every ray of 
radiant heat would be intercepted by it. Taking the case 
of a room 36 XQ x7 feet, with 60 quarters hanging therein, 
and allowing free circulation all round, the additional sur- 
face exposed to the emission of heat from the radiants 
would be (34X3%4'5 feet) + (20 x 2°6 x 4'5)=684 feet of 
