509 



whereby it is speedily dried, and not subjected to the escape of any of 

 its constituent parts, except that of water. The fruit is i^reserved in its 

 purity, to be restored to its original condition when again subjected to 

 water. 



It is not my province to exercise any judgment, nor do I purpose to 

 express any opinion of the relative merits of these patented machines, 

 but only to communicate to the agricultural community an idea of the 

 mechanical structure of them, that they may judge of their moile of op- 

 eration, their efficiency, and their practical usefulness. 



Of the first two viamed, Alden's and Smith's, while I readily observe 

 the differeuce in their mechanical operation, 1 confess I cannot perceive 

 any difference in the principle which governs the application of heat, 

 or the result obtained. Each consists of a vertical square box of wood, 

 lined with galvanized iron, varying in height from fifteeu to five and 

 twenty feet, in which is hung a series of shelves, about nine inches apart, 

 upon which is i)laced the fruit, or vegetable to be dried, and at the bot- 

 tom of which artiticial heat is applied.* These shelves, made of wire or 

 of any perforated material, are moved up and down, in one case, by an 

 attachment to an endless chain, and in the other, by a screw. The 

 green fruit is placed upon these shelves at the bottom, or at the top, as 

 the case may be, and taken out at the bottom or top when sufficiently 

 dried. The shelves are moved up and down by a crank, the speed of 

 which is governed by the necessity of the case and the judgment of the 

 operator. Each of these machines is large or small as the exigencies 

 of the case require a greater or less amount of work to be done. And 

 their cost is in the same proportion, varying from one to five thousand 

 dollars. 



The machine of A. J. Eeynolds differs essentially from the others in 

 its application of beat. Its shelves of fruit, operated also by a crank 

 and cog-wheels, have a rotary motion ; the heat is introduced at the bot- 

 tom of a cylinder, which may be of a size proportioned to the amount of 

 work to be done, within which rotate the fruit-shelves upon a spindle which 

 supports them, and in the center is a hollow drum, whose only office is 

 to occupy space, and thereby confine the heat to the material to be dried. 

 Unlike the machines of Alden and Smith, before described, the vapor 

 created by the heat and process of drying is not allowed to escape di- 

 rectly at the top, but is there conducted into condensing tubs of water 

 and flows off gradually. The shelves of fruit, when dried, are all 

 removed at once by opening a door of one side of the outer cylinder. 

 Heat is also introduced into the side of this machine through the medium 

 of the smoke-pipe, which passes up alongside of the outer cylinder. It 

 is claimed for this machine, that it consumes less fuel and diffuses the 

 heat more generally and continuously than any other; that it may be 

 u^ed of so small a size as to be adapted to the top of a common stove, 

 and from such a size up to the largest, which is 10 feet rn diameter and 

 16 feet high. The price varies from fifty to twelve hundred dollars. 



When \Ve consider the great importance of the desiccation of fruic and 

 vegetables effecting the saving of so large a portion which is now lost; 

 for keeping them for any length of time, and in all weather and climates, 

 and in view of their transportation, (their weight is reduced at least 

 three-fourths,) too much importance cannot be attached to the subject. 



I would have been pleased to have furnished drawings of each of 

 these machines, whereby they might have been better understood, but 

 only that of "Keynolds's Improved Evaporator" was at liand, and that 

 is herewith given. 



