268 HORTICULTURE FOR SCHOOLS 



peaches, plums, and prunes, and least significant in the case 

 of the harder and slow-ripening sorts such as apples, some 

 varieties of pears, and the citrus fruits. 



381. The temperature element. Next to the type of 

 handling given the fruits, the most important factor in their 

 sound transportation to market and storage is the tempera- 

 ture at which they are held. As warmth favors decay, cold 

 checks it. The temperature factor is very important for all 

 fruits, but it would be impossible to transport the soft fruits 

 to market without some means of cooling and keeping them 

 cool during the trip. This is the purpose of the modern 

 refrigerator-car. 



382. History of refrigeration. The refrigerator-car was 

 invented in the middle of the last century but did not come 

 into general use until the decade beginning 1870. During 

 these ten years the meat-packers and shippers adopted the 

 car very generally, and in the next decade, from 1880 to 1890, 

 the shippers of fruit followed their example. 



At first objections were raised to the building of these 

 expensive cars on the ground that they could be used for a 

 limited time only in each year. This has not proved to be the 

 case. The season for perishable products opens in the United 

 States in Florida in late winter. The railroads estimate that 

 it then moves northward as the season advances at the rate 

 of about fifteen miles a day. Meanwhile the refrigerator-car 

 follows this advancing season and is used to haul the fruit 

 from each section successively. Finally, the cars which were 

 employed in the beginning of the season to haul the fruit from 

 Florida northward, are used later to carry the northern prod- 

 ucts southward. It has now been found that in addition 

 to keeping the fruit cool, these cars can be used during the 

 fall and winter in the North for the transportation of products 

 which otherwise would be frozen by the extreme cold. The 

 same construction which in summer excludes the heat is 

 utilized in the winter to keep the warmth in the car. 



