Introduction and Background

A PROCESS OF OBTAINING A DRY.COLD CURRENT OF AIR. FROM ICE, ITS DIFFERENT APPLICATIONS. INVENTED BY JOHN C. SCHQOLEY. epeJ2%% Patented March 13th, 1855. CINCINNATI: ABBOTT & KINNEY PRINTERS. + 1858. JOHN C. SCHOOLEY’S PROCESS OF OBTAINING A DRY COLD CURRENT OF AIR FROM ICE. HISTORY AND PRACTICAL RESULTS. During the summer of 1848 I made an experiment in producing a cold atmosphere from ice, and applying the same to Refrigerators or Ice Chests; by placing the ice at the top of the apartment to be cooled, and producing my temperature by conduction. Although this had been accom- plished before, yet I hid an idea of ventilation by construct- ing tubes, leading from the cooling chamber up through the i¢e, also tubes leading directly up from the ice chamber; however, before T had completed the Refrigerator I dispensed entirely with the tubes leading from the cooling chamber, but allowed the others to remain. This Refrigerator is now in use, but has never proved of much account, although it preserves provisions with as much success as other Reftig- erators of the diy. My aim was to get clear of the moisture, and produce a dry atmosphere; which I did not accomplish. My business being that of packing and curing Pork and Beef during the winter, and having examined into all of the processes of summer curing with ice, I was confident if the same temperature from ice could be obtained without the 9 moisture, Pork and Beef could be cured as well in summer as in the winter. The following spring I proposed to 2 friend (who was in the ice business, and who contemplated erecting a pork house and ice house adjoining cach other) to make his pork house cellar the same depth as his 1¢e house, and to construct an opening between the two, 8° that he could use the cold air from the ice in the curing of meats during the summer. The building was erected and the door way made, but in consequence of the risk to be incurred in making such an experiment of curing & sufli- cient quantity of meat in this air so produced, the trial was not made until March, 1854, at which time T took possession of the buildings, and being satisfied that my theory was correct, I embarked in the enterprise. I first made the ceiling of the cellar tight by closing the openings, such us hatchways, stairways, &e.; also constructed a ven- tilator leading from the top of the cellar up to and through the roof of the building; made with valves, so as they could be closed or opened at will. I then made my contracts for hams and shoulders to be delivered fresh from hogs killed every day throughout the summer, and put the first meat in salt on the 21st of March, 1854, and continued until T had invested about $5,000. My temperature was now 40', and a strong current of air rushed in from the ice cellar through the opening continually, and as it became warmer ascended and passed out of the ventilator; thus keeping up a current of cold atmosphere. I discovered no conden- sation in my curing chamber, but, on the contrary, the moisture brought in by warm meats, &e., was absorbed and carried off; the salt on my meat sometimes cracked, as it always does just preparatory to freezing; which was a con- vincing proof of the presence of a dry atmosphere, and that my plan would result successfully. After some twenty-five 3 days from the first salting, I commenced taking out the salted hams and shoulders for the smoke house, where the results of my operations were to be ascertained, and found that my losses by spoiled meat were far less than I had anticipated. My second smoking in May, produced much less per centage of spoiled meat; my third smoking in June, showed a loss of not exceeding seven per cent. of hams, and six per cent. of shoulders; my fifth smoking still reduced the per centage. These losses were calculated out of the smoke-house, not out of salt. During the entire summer I met with the same success, and before the end of the warm months I had cured successfully upwards of jifteen thousand dollars worth of pork, with a loss of spoiled meat averaging not over seven per cent. It must be taken into consideration that a great portion of summer pork is from slop fed hogs, and the meat is more difficult to save than com fed, even in the winter season. In the winter if com fed hogs are killed and put in salt in cold dry weather, there should be no loss in spoiled meat, but the general average of loss throughout the season of killing and curing in all kinds of atmosphere, is from two to five per cent. It is therefore evident, if we take into consideration the differ- ence in the quality of the meat, that my process has re- duced the summer curing equal in success to that of winter curing. Later in the summer my temperature was 52°, (caused by a deficiency of ice, it being owned by other parties who were in the ice business, and who were contin- ually disposing of it,) and in this degree of cold I was com- pelled to cure my meat until another ice house could be procured. I soon obtained one, which was arranged upon the old plan, with the ice over head, and the temperature produced by conduction; although the apartment was sufli- ciently cold, the atmosphere was exceedingly moist and 4 impure, with the condensatiun hanging in drops on the ceiling, and running down the sides of the walls; here I lost from twenty to twenty-five per cent. in a temperature of 39° and 40°, and here as in my own house, the ice was taken out, (being sold by the owner at some $20 per ton) causing my temperature to be 52° with a moist atmosphere ; which state of things continued some thirteen days. T now had an excellent opportunity of ascertaining the difference of curing meats in a dry and moist atmosphere with the following results: In my cellar at 52°, the air being free fiom moisture, my losses were only nine per cent. and in the moist air, at same temperature, sixty-seven per cent. in shoulders, and sixty per cent. in hams, or nearly three- fourths of the entire meat received during the thirteen days. At the close of the summer, those who had opposed my un- dertaking commenced to look favorably upon it, and some eyen went so far as to take drawings of my plans with a view of eventually using the same for their own operations. I at once determined to apply for a patent for my process of producing a dry cold atmosphere, so as to apply it to Re- frigerators, preservation of fruits, &e., I therefore filed my caveat immediately, and on the 13th of March, 1855, re- ceived my Letters Patent. I had submitted my plans and * explained my theory to several scientific gentlemen, all of whom looked upon my invention as one of great usefulness, and destined to be of considerable value. It is a well known fact in Natural Philosophy, that the atmosphere contains variable quantities of moisture ; that its capacity for retaining that moisture depends much upon its temperature. If the air be brought in contact with bodies much colder than itself, its capacity for retaining the aque- ous vapor is diminished 5 consequently there will be a deposit of dew, the air thereby becoming drier. As this dried air 5 becomes warmer, its capacity for moisture will be of course inereased, and it will therefore absorb any moisture with which it may come into contact. It is also a well known fact, (with only one exception,) that the specific gravity of bodies is increased in proportion to the diminution of the temperature—that is, they con- tract, and of course occupy less space. It is upon these two philosophical principles that I have constructed my “MEAT, PROVISION AND FRUIT PRESERVER.” I pass the air over the surface of ice, which condenses the moisture it may contain; at the same time the air becomes specifically heavier, and then flows into the cooling chamber, where it necessarily becomes warmer and lighter, and, its capacity for moisture increased, it ubsorbs all of the moisture that may be present in the apartment, then ascending passes out into the external at- mosphere, thus producing a cold dry current of air contin- ually through the cooling chamber, The temperature in my curing apartment during the summer ranged from 39 to 48 degrees whilst it was 90 to 95 degrees in the shade outside; and was entirely free from moisture, must, or any impure air, whilst in all other places heretofore used for summer curing, the curing cham- ber was constantly kept damp by the dripping from the ceiling or a stream of condensed vapor running down the sides of the apartment—creuting an impure atmosphere ; the result of curing in this moist air was most disastrous, which has heretofore prevented the summer curing process from being of any comnurcial value. My plan can be seen in full operation, on a large scale, at any time from the Ist of April until Ist of November, at my establishment, No. 859 Plum street, Cincinnati, O. The following letter is a review of my process and inven- 6 tion by Professor J. M. Locse, Analytical Chemist, Miner- alogist, &e., Cincinnati, Ohio. Cincinnati, February 13, 1855. Dean Sim—After having examined your plan for curing meat and preserving all kinds of fruits and provisions during warm weather, Thave written down the ration- ale of operation and the authority for the principles involved. i Tet, There will bea current of air established down through the ice, theuee into the curing or preserving room, from which it will pass up the ventilator. The reason of this action is this, The air in the interstices of the iee gives out its heatto the ice Which it melts, and theheat becomes latent (or hidden) in the water thus produced; the ice by being thus cooled is contracted in bulk, and therefore denser, and as all dense substances, it settles to the bottom, and flows into the euring room. By attempting to assume a level in this room it meets with bodies, such as meats, &c., which is warmer than itself, from these bodies it absorbs heat and expands, (Authority, Gra- ham's Blements of Chemistry, page 40, Philadelphia, 1852, Muller's Physics, page 463, 1648, and Olmstead's Philosophy, atticle 475, N. Y., 1845, and Puuledt, a Paris, S16.) ‘The expanded or rarified particles ascend to find an equilibrium, and thus ascond to the top of the veutilator. ‘This action is coutinuous Pic, 1, and produces a curreut without the aid of any mechanical mat- ter. (Authority, article 476, On Ventilation of Mines, in Olm- slead’s Philosophy. This can be easily iNustrated by taking a J shaped tube, as in Fig. 1, and place some mereury in the curved part, then pour water in the long leg at A, the mereury would tise about one inch in the leg C for each foot of water in |A, ou account of the difference of their density; now suppose the lez Cto be the ice room and to have the power (as has been seen before) of condensing the air, which would therefore support a taller column of ratified ai but if the column A is not sufli- ciently tall to hold quantity of the rarified air to balance the dense air in C, then it would be forced out aud produce a current. This is the action in the ordinary chimney. Qd. Air can only hold a certain proportion of vapor of water suspended in it according to its temperature, the lower the temperature the less is it capable of holding, for we determine the quantity of moisture which the air contains by ob- serving at what reduced temperature it commences to deposit it as mist or dew. (Daniel's Meteorological Essoys, page 147.) Muller says, ‘If on a hot summer’s day, at a temperature of 77 degrees, every cubic metre of air contains 13 grams (200,76 grs.) of vapor, we say the air is very dry, for at such a temperature the at- mosphere can contain 22.5 grams of vapor for every cubic metre of air, otherwise the air must be cooled to 59 degrees, in order to be saturated by the same quantity of aqueous vapor; if, on the contrary, in winter, at a temperature of 3596, the air contains only 6 grams of vapor, itis very damp, since the atmosphere is neatly per- fectly saturated with vapor, corresponding to that temperature, and the least decrease of temperature is followed by a precipitation of moisture.””—Muller, page 594. We will now attempt to apply those facts to our purpose; when the air passes: amongst the pieces of ice, its temperature is reduced, anda large portion of moisture 7 deposited, as its capacity for holding aqueous vapor has been decreased. Tt then enters into the curing rooin where the temperature is enhanced as before mentioned, and it then has power to absorb additional aqueous vapor, which it does and is car- ried off, as previously mentioned. Let us for a moment look to the action; if the curing room was surrounded by or the ice was placed at the top, as in the Baltimore, or other old plans, which produce their temperature by conduction; if we had the ventilator in these cases, we would have the current reversed. ‘The air which passes into the room docs not come in direct contact with ice, and all of the moisture of this ingressing air would be de- posited in the curing room, whereby instead of drying it, it would add moisture. Some would probably object to the air not passing through your room with greater speed, but Graham’ settles this, by stating “It should be kept in mind that a certain time must elapse before air is saturated with humidity. Mr. Daniel has observed that a few cubic inches of dry air continued to expand for an hour or two when ex- posed to water at the temperature of the air.” Graham's Elements of Chemistry, page 95. ‘The following are what I conceive to be the advantages of your arrangement: Ist, You establish a current without other means than those which Nature fur- niches. 2nd, All the cooling effected by the melting of the ice is applied in the curing room. 3rd. There is a current of airin the curing room which wastes none of its cooling properties, and furnishes fresh air to operations. 4th, ‘The curing room is kept dry, and things which are moist when placed therein are dried. Yours, most respectfully, JOSEPH M. LOCKE. Jous ©. Scroorzy, Bsq., Cincinnati. Tt is well known that in preserving meats from decom- position from the effects of heat or a high temperature that ice has been used and applied in a variety of forms, but not sufficiently successful to render any of the methods used of any commercial value. It has been found in curing meats in particular that the atmosphere should be ina certain con- dition to render it successful. The conditions are first, a certain degree of cold, and, secondly, a certain state of dry- ness, and without these conditions, all will prove a failure if attempted. For instance, a temperature of 48° is suflicient- ly cold, but dampness even at that degree of cold will make it prove a failure, that is, there will be such a quantity of spoiled