102 BOAED OF AGRICULTURE. 



the principle to be correct, we fear that the constant and untir- 

 ing watchfuhiess necessary for its success will so seldom be 

 given, as to prevent their general use. Other houses, controlled 

 by ice, for the preservation of fruits, are in successful operation 

 in Philadelphia, but these arp subject to ventilation, reliance 

 being had on a proper supply of cool, pure air. We tasted 

 specimens from these of the Northern Spy and other apples of 

 the growth of 1868, in September last, in most excellent pres- 

 ervation, both as it regarded beauty and flavor. One of the 

 Philadelphia houses preserves a working temperature of about 

 35° of Fahrenheit, the other 40° ; but both are operated with- 

 out any artificial dryer or absorbent, while Mr. Nyce's house is 

 kept at 34°, and involves the use of chloride of calcium, to ab- 

 sorb any superfluous moisture from the air. In regard to the 

 temperature, the object is to hold the ripening process in equi- 

 librium, at a point neither much above nor much beloiv, for, with 

 an increased temperature, maturation would take place, and, 

 with too low a rate for considerable time, the fruit would be- 

 come materially affected in its quality. A temperature of 40° 

 will hold the ripening process in suspense ; but when tlie fruit 

 is wanted for use it should be removed to a temperature of 55° 

 or 60°, and ripening will succeed. 



Various substances have been used for the packing of fruit, 

 such as sand, charcoal, sawdust, chaff", &c., &c. None of these 

 will preserve it for any considerable length of time, unless the 

 temperature of the apartment is at the right point ; but when 

 this is attained superfluous substances are unnecessary, and are 

 frequently positively injurious. In regard to temperature, dif- 

 ferent varieties require different degrees of heat, according to 

 the firmness of the skin and the texture of the flesh. 



Farmers understand pretty well how to keep their apples 

 during the winter season by storing them in cool northern cel- 

 lars ; but the preservation of the pear and other delicate fruits 

 is more difficult. For instance, the pear is a better conductor 

 of heat than the apple, as may be seen by tasting specimens 

 kept in the same temperature, the pear appearing the coldest to 

 the taste. Owing to this better conducting power, it is more 

 quickly affected by changes of temperature, and hence more 

 difficult to keep. 



