FARM HANDICRAFT FOR SCHOOLS. 19 
slivering. Bore the holes straight into the wood. See directions on 
page 5. To aid you in boring the holes to the exact depth desired, 
bore a f-iiich hole lengthwise through a piece of scrap lumber 1J by 
H by 4 inches, and slip this on the shank of the bit to form a collar; 
the bit should extend 2f inches beyond the collar. Bore a trial hole 
in a piece of scrap lumber with this collar on the bit; if the hole is 
too shallow, cut off the end of the collar to get the correct length; 
if the hole is too deep, make another collar. After the holes are 
bored, trim the edges along the sides of the piece until each opening 
is f inch wide. Paint or stain the case; this will improve its appear- 
ance as well as preserve the wood. 
Note to Teacher. — Collections of seeds are very useful aids in teaching agricul- 
ture. A pupil will get a much better idea from examining the seeds themselves than 
by reading about them. If you are to do efficient work in- crop studies, you must 
have the seeds and, moreover, they must be arranged in some kind, of order and be 
of convenient access. The seed sample case solves the question of a place in which 
to put the seeds. For an extended discussion of this subject see Farmers' Bulletin 586. 
Descriptions of weed seeds and methods of eradication are good 
topics for written lessons. Many weeds have been introduced into 
the United States from foreign countries; the Russian thistle, for 
example. A study of the climate and plants of these countries will 
add to the interest of the geography lessons. Enlarged drawings of 
seeds as they may be seen under a lens are useful, not only for their 
agricultural value, but for the drawing lessons as well. 
EXERCISE VII. HOTBED AND COLD FRAME. 
A hotbed is a bed of fertile soil surrounded by a glass-covered 
frame, usually of wood, and heated artificially. As a rule fresh stable 
manure is placed in the bottom of a hotbed as the source of heat. 
A cold frame is a box-like frame covered with glass or muslin. These 
frames are similar to hotbeds except that no heat is supplied artifi- 
cially. The sun's rays through the glass are depended upon as the 
source of heat. The principal use of hotbeds is for the production 
of plants for early setting. Cold frames are used primarily to harden 
off plants that have been started in a hotbed. They are used also 
to mature crops earHer in the season than if they were grown in the 
field and to lengthen the growing season of certain crops that do not 
normally mature in a given locality. Temporary cold frames are 
sometimes built over partly grown crops in the field; lettuce, for 
example, for the purpose of protecting the plants during the cold 
weather of early spring and hastening their growth. Hotbeds and 
cold frames should be set in well-drained soil and should slant toward 
the south. 
The most common sash used for hotbeds and cold frames is 3 
feet wide and 6 feet long, with the side pieces, known to gardeners 
as stiles, extending 2 inches, beyond the ends. These projections 
