282 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



Dryness is its leading- pateiitaMe feature. Vapor is constantly given oif 

 from dilfcrent kinds of fruit, amounting usually to at least lialf a gallon of 

 water from one hundred bushels, per week. This vapor is taken up by the 

 absorbent, which is spread over the floor of the fruit room. It is made to 

 run out in tubes to the outside, once in about every month. It is then 

 dried in large pans of sheet iron, and returned to the house in the dried 

 state as before. The same substance is thus used twenty or thirty times. 

 The air in a room so completely confined, after tlie fruit is chilled down to 

 34 deg., becomes very still. The fans are needed to give circulation to the 

 air, and bring the moisture arising from the fruit in contact with the ab- 

 sorbent, to be taken up by it. 



The air is pure, because every source of impurity is excluded. 



In the gradual ripening of fruit, hydrogen and carbon are constantly 

 given off; the former unites with the oxygen of the air, and forms water; 

 the latter, carbonic acid. 



This process in any confined vessel filled with fruit, consumes all the 

 oxygen, especially if the fruit be ripe and the air warm, in about 48 liours. 

 The rooms of this house are gas tight, and when filled with fruit, if closed 

 up for two days, a candle goes out in them almost instantly. 



The fruit is then surrounded by an atmosphere composed of the nitrogen 

 of the air and carbonic acid. The former is destitute of all active proper- 

 ties, good or bad. The latter is not suflScicntly acid, unless under heavy 

 pressure, to produce any action on fruits immersed in it. Hydrogen and 

 carbon then cease to be evolved from the fruit, as there is now no agent to 

 unite with them, in the same way that thfey cease to be evolved from a 

 burning candle when the air is removed. Decomposition ceases in both 

 cases, and for the same reason. The principle is thus stated by Liebig: — 

 " Decay is much retarded in the absence of moisture, and by the substance 

 being surrounded with an atmosphere of carbonic acid, which prevents the 

 air from coming in contact with decaying matter." 



The sources of profit are pears and grapes, kept during the fall and win- 

 ter months; apples until the months of May, June and July; lemons, oranges, 

 pine-apples, through the summer season; canned fruit, put up in si'x or ten 

 gallon cans, and retailed out by measure ; the fruit when taken from the 

 cans, which are used successively for a number of years is kept fresh in 

 the house in the open vessel for a number of weeks. Hence this fruit may 

 be sold by measure without loss in the summer months. Oysters, butter 

 and eggs, are also sources of f)rofit. 



All fruit should be in the hbuse when tree-ripe, that is as soon as it has 

 received all the virtue the tree or the vine can impart to it. " Rub an ud- 

 ripe or green apple or pear on a grater to a pulp, wash this with cold 

 water on a fine sieve, the turbid liquor which -passes through deposits a 

 fine flour of starch, of which not even a trace can be detected in the ripe 

 fruit. This after-ripening, as it is called, is purely a chemical process. It 

 is the starch being transformed into sugar; the more starch the unripe fruit 

 contains, the sweeter does it become when ripe." — Liebig. 



Although after the saccharine change, putrefaction may go on slowly at 

 34 degrees, yet starch is much more slowly changed into sugar at that 

 temperature. In strict accordance with this principle, it is found that the 



