COLLECTING AND PRESERVING. 189 



bottom. The sides of the trough are made of thin bits of board, 

 3 or 4 inches wide and a foot or more long. These sides have 

 very little slant. The crack in the bottom of the trough is left 

 about a half -inch wide, and it is covered beneath with a strip of 

 cork. The body of the insect is now placed lengthwise the 

 crack, a pin is thrust through the thorax, or middle division of 

 the insect, into the cork, and the wings are laid out on the sides 

 of the trough. The wings are held in place by strips of card- 

 board pinned over them. Take care not to stick the pins 

 through the wings. In about two weeks the insects will be 

 dry and stiff. 



Insects must be kept in tight boxes to keep other insects 

 from devouring them. Cigar boxes are good. Tight boxes 

 with glass covers are generally used by collectors. Place sheets 

 of cork in the bottom of the box to receive the pins. If insects 

 attack the specimens, expose them in a tight box to vapors of 

 bisulphide of carbon (see Chap. I, ) or benzine. 



5. Preparing Old Bottles for Specimens. 



CUTTING GLASS BOTTLES. 1. Pass 5 or 6 strands of coarse 

 packing-twine round the bottle on each side of the line where 

 you want it divided, so as to form a groove inch wide ; in this 

 groove pass one turn of a piece of hard-laid white cord, extend 

 the two ends, and fasten to some support. Saw the bottle back- 

 wards and forwards for a short time ; after a minute's friction, 

 by a side motion of the bottle throw it out of the cord into a 

 tub of water, and then tap on the side of the tub and the 

 bottom will fall off. 



2. Fill the bottle the exact height you wish it to be cut, with 

 oil of any kind ; dip, very gradually, a red-hot iron into the oil. 

 The glass suddenly chips and cracks all round, then the upper 

 surface may be lifted off at the surface of the oil. 



3. For cutting off bottoms of bottles, make a slight nick with 

 a file, and then mark round with a streak of ink where you 

 want it to come off. Make an iron red-hot and lay it on the 

 nick. This will cause it to expand and crack ; then, by moving 

 the rod round, the crack will follow. 



