MEANS OF PREVENTING FROST. 



335 



"been reached. It consists of a thermostat, 

 an electric battery, and an electric bell. The 

 thermostat is provided with a metallic scrip 

 .clamped at one end. A change of rem- 



BatUrjf 



perature causes a bending of the strip so 

 that it touches the point of an adjustable 

 screw and makes electric coriS;act. The 

 thermostat should be placed outside, while 

 the battery and the bell may be placed in the 

 bedroom. As soon as the temperature out- 

 side falls to 32 degrees the thermostat mukes 

 the circuit and rings the bell. The rest de- 

 pends upon the man who is rung up. 



There are several practical methods of 

 preventing frost, or if frost has occurred, 

 of preventing fatal injury to plants. Among 

 these methods a few of the more important 

 may be mentioned : 



I. WARMING THE AIR. 



A large number of small fires, properly 

 placed, will raise the temperature of an or- 

 chard or garden several degrees. Under 

 this head various methods have been tested 

 in California, and the best has been that of 

 suspending wire' baskets a few feet from 

 the ground, each holding several pounds of 

 charcoal or other suitable fuel. The bas- 



kets may cost 10 cents each, and if 40 bas- 

 kets were used per acre, the fuel would cost 

 $2.50 or $3.00. 



2. PREVENTING RADIATION. 



A cloudy sky at night is often effective 

 as a prevention of frost. Adopting tkis 

 idea, the fruit grower may create clouds of 

 smoke in the orchard by setting fire to pre- 

 viously prepared smudge piles, consisting 

 of damp straw or strawy manure. The ef- 

 fect of both of the above methods will de- 

 pend upon the existence of air currents. 

 For best effect the air should be still. 

 3. WATERING TREES AND PLANTS. 



Injury from frost may often be prevented 

 by sprinkling. This, of course, is practi- 

 cable only where there are waterworks, and 

 then only on a small scale, but may be used 

 for gardens and flower beds. This should 

 be done in the evening before frost is ex- 

 pected. If, however, no precautions have 

 been taken and plants have been frozen, 

 fatal injury may often be prevented by 

 sprinkling very early in the morning before 

 the temperature begins to rise — before sun- 

 rise. It is believed to be the rapid rise of 

 temperature before the injured cells have 

 time to readjust their functions, that causes 

 injury. The blanket of water prevents the 

 rapid heating. 



It may be said in conclusion, going back 

 to the question of forecasting, that the daily 

 forecasts published by the weather bureau 

 at Toronto should be followed closely. Be- 

 sides being published in the daily papers, 

 these forecasts may be secured by telephone 

 from the nearest telegraph office. With the 

 extension of rural telephones the important 

 service rendered by the weather bu'cau 

 may be brought within reach of every rural 

 district in Ontario. 



Power Spraying. — With the advent of 

 the power sprayer in the course of a year or 

 two we will have these power machines 

 workings in sections where a few thousand 



trees can be found within a square of six to 

 eight miles, just as we have threshing ma- 

 chines working to-day. — (Frank J. Baker, 

 Georgetown, Ont. 



