EVAPORATION OF FRUIT. 403 



ment necessary, which sometimes amounted to actual want. When, 

 in 1881, the steamer " Rodgers" was ready to sail from San Fran- 

 cisco in search of the " Jeanette" it was detained for eight days by 

 the discovery that of the stock of canned goods on board 4000 

 cans were leaky, and contained provisions already in a state of 

 decay. Every sea-captain can tell of the same kind of experience. 

 The blame rests partially upon the manufacturers who permit the 

 work to be done carelessly, and do not take into consideration that 

 the slighest access of air spoils the contents of the can, but par- 

 tially also upon the mode of preservation itself, because even 

 faultlessly closed cans have the disadvantage that when once 

 opened their contents must be immediately used, while the packages 

 containing evaporated fruit may remain open for years in every 

 climate. Moreover, in eating the latter, lead poisoning need not 

 be feared, and, as previously stated, it has the further advantage 

 of a great reduction in the cost of freight. Green peas, of which, 

 as is well known, immense quantities are canned, may serve as 

 another example. In the canned state seven boxes of them weigh 

 350 Ibs., while one box of evaporated peas, which contains the 

 same quantity of substance, but deprived of its content of water, 

 weighs only 43 Ibs., though when placed upon the table there is 

 not the slighest difference as regards quality between the two 

 articles. Taking into account all these advantages, and considering 

 at the same time that by a good method of drying the hazards 

 and annoyances connected with the preservation of fruit in a fresh 

 state can be largely overcome, it must be concluded that the 

 evaporating process is destined to play in the future a still greater 

 part in the preservation of fruit than it does already at the 

 present time. 



Before entering upon a description of the apparatus and its use, 

 it will be necessary to explain the principle upon which it is based 

 and the theory of evaporating fruit. 



The object to be attained is not only to make the fruit keep, 

 but also to retain the properties for which it is valued. This can 

 only be reached by withdrawing the content of water, and at the 

 same time converting a portion of the starch into sugar in as short 

 a time as possible without boiling the fruit. The latter would 

 injure the taste of the fruit, and slow drying gives a flavor calling 

 to mind decay. The quicker the watery portions are removed 



