INSECT POWDERS: See Insecticides.
INSECT TRAP.
Into a china wash-basin, half filled with water, pour a glass of beer; cover the basin with a newspaper, in the center of which a small round hole is cut. Place it so that the edges of the paper lie on the floor and the hole is over the center of the basin. At night beetles and other insects, attracted by the smell of beer, climb the paper and fall through the hole into the liquid.
INSTRUMENT ALLOYS: See Alloys.
INSTRUMENT CLEANING: See Cleaning Preparations and Methods.
INSTRUMENT LACQUER: See Lacquers.
INSULATION
Electric Insulation:
Insulating Varnishes.
I.—Melt 2 parts of asphalt together with 0.4 parts of sulphur, add 5 parts of linseed-oil varnish, linseed oil or cottonseed oil, keep at 320° F. for 6 hours; next pour in oil of turpentine as required.