that if we hear a clap of thunder half a minute after the flash, Food for 

 we may calculate that the discharge of electricity is six and a Plants 

 half miles off. 205 



Lightning can be seen by reflection at the distance of two 



hundred miles. 



The explosive force of closely confined gunpowder is six and 

 a half tons to the square inch. 



How to Preserve Eggs. 



To each pailful of water, add two pints of fresh slacked lime 

 and one pint of common salt; mix well. Fill your barrel half full 

 with this fluid, put your eggs down in it any time after June, and 

 they will keep two years, if desired. A solution of silicate of soda, 

 commonly known as water glass, is also used for the same purpose. 



Estimating Measures. 



A pint of water weighs nearly 1 pound, and is equal to about 

 27 cubic inches, or a square box 3 inches long, 3 inches wide and 

 3 inches deep. 



A quart of water weighs nearly 2 pounds, and is equal to a 

 square box of about 4 by 4 inches and Q/2 inches deep. 



A gallon of water weighs from 8 to 10 pounds, according to 

 the size of the gallon, and is equal to a box 6 by 6 inches square 

 and 6, 7 or 7^ inches deep. 



A peck is equal to a box 8 by 8 inches square and 8 inches 

 deep. 



A bushel almost fills a box 12 by 12 inches square and 15 

 inches deep. In exact figures, a bushel contains 2150.42 cubic inches. 



A cubic foot of water weighs nearly 64 pounds (more correctly 

 623^2 pounds), and contains from 7 to 8 gallons, according to the 

 kind of gallons used. 



A barrel of water almost fills a box 2 by 2 feet square and 1^ 

 feet deep, or 6 cubic feet. 



Petroleum barrels contain 40 gallons, or nearly 5 cubic feet. 



Square Measure. 



144 sq. in. — 1 sq. foot 160 sq. rods — 1 acre 



9 sq. feet — 1 sq. yard 43,560 sq. ft. — 1 acre 



3034 sq. yards — 1 sq. rod 640 acres — 1 sq. mile 



2.47 acre — 1 Hectare. 



