134 BEEHIVES AND BEE KEEPERS' APPLIANCES. 



of the sun are luminous, but those which are 

 radiated from a comparatively dull substance are 

 opaque. For instance, in a greenhouse the heat 

 is found to be very much more oppressive than 

 in the hottest place outside. This principle is 

 utilised in the solar extractor (Fig. 125). The 

 appliance consists of a box formed with a sloping 

 top like a desk, the top being glazed with a 

 double thickness of glass as shown by Fig. 126. 

 The dimensions may vary considerably, but those 

 given in Fig. 125 will make a very useful and 

 practicable size, namely, length, 20 in. ; breadth, 

 12 in. ; height at back, 12 in. ; at front, 6 in. 



Fig. 125. Solar Wax Extractor. 



It should be made of very sound and dry stuff, 

 preferably yellow pine, and it would be well to 

 dovetail it together at the corners. The bottom 

 should be grooved and tongued at the joint, or 

 else made of one piece of wood. It would be a 

 great improvement to line the whole structure with 

 tinplate, which would ensure its being wax-tight. 

 The top consists of a frame of 2 in. by 1 in. stuff 

 mortised together at the corners, and rebated to 

 take the glass, the rebate being f in. by J in. The 

 glass is to be placed in a slight bedding of soft 

 putty, and then a strip f in. by \ in. is to be tacked 

 to the frame close up to the glass ; the other glass 

 is then to be put in a similar bedding of putty, 



