56 The Fruit-Growers Guide-Book 



are more familiar with its combustion. In the work of 

 orchard heating it has given great satisfaction, and many 

 hundreds of acres of orchards have been kept from frost 

 ruin by coal burners. 



When oil costs 3 cents per gallon, and coal can be 

 had for $5.00 per ton, it is the opinion of persons who are 

 sufficiently experienced that coal is the cheaper fuel. 

 Heaters are so constructed that they will burn about five 

 pounds per hour, and at this rate, a heater holding fifty 

 pounds will burn through most any one of the cold nights 

 in spring without the necessity of refilling. 



One of the great advantages in using coal for fuel, is 

 that no expensive storage tanks are necessary, and no 

 special equipment needed to enable the orchard man to 

 carry it to the pots in the orchard. It can be kept in a 

 pile at a convenient place in the orchard, merely covered 

 with canvas or boards to protect it from the weather. 

 Where oil is used some special means of storing must be 

 had, such as a cement cistern or large iron tank, or even 

 in numerous barrels, and for distribution there needs to 

 be a special tank wagon. Coal, on the other hand, can be 

 hauled in an ordinary wagon box, or what is better in a 

 low sled, so as to enable one to get at the coal with the 

 least amount of labor. 



Heaters of this class require some special fuel for start- 

 ing the fires, and this is most easily obtained from kindling 

 made from broken-up bits of pine or from the tree trim- 

 mings that have been kept in a dry place. A bit of cotton 

 waste should be soaked in oil and placed in the bottom of 

 the heater, and on top of it a generous amount of kindling, 

 with the coal on top of that. Egg or small lump coal is 

 the best and should be handled with a fork so as to avoid 

 the slack and small pieces that clog the fire and make it 

 burn too slowly. The coal should be piled in the heater 

 so as to leave the center open and afford a draft, and also 

 to allow some of the coal to remain on the side of the 

 heater, where it will be in reserve. 



With coal burning heaters it is the general experience 

 that fifty per acre will generally suffice to hold the tern- 



