THE London JOURNAL OF ARTS AND SCIENCES. No. LXXVIII. Recent Patents. To JAMES YANDAL, of Cross Street, in the District of. St. John's, Waterloo Road, in the County of Surrey, Private person, for his Discovery of an Improvement or Improvements on Apparatus for Cooling and Heating Fluids. [Sealed 24th August, 1826.] THIS is an apparatus designed for cooling worts and other hot fluids, without exposing them to evaporation. Utensils employed for this purpose, are generally called refrigerators, and are so constructed, that a quantity of cold water shall be brought in, contact with the vessel which contains the heated fluid. But in every construction of refrigerator heretofore used, the quantity of cold water necessarily employed in the operation, greatly exceeded the quantity of the fluid cooled, which, in some situations where water cannot be readily obtained, is a serious impediment and objection to the use of such apparatus. The inventor has contrived a mode of constructing a refrigerator, so that any quantity of wort or other hot fluid, may be cooled by an equal quantity of cold water; the process being performed with great expedition, simply by passing the two fluids through very narrow passages, in opposite directions, the result of which is, that the cold liquor imbibes the heat from the wort, or other hot fluid, and the temperature of the hot fluid is reduced in the same ratio. ་ The patentee commences his specification by saying, Previously to describing my improved apparatus, I think it right to make a few observations on my discovery, and the general nature or principles upon which my apparatus is constructed. If two fluids of different temperatures be brought nearly together, separated only by a thin metallic partition, and the surfaces of the two fluids be greatly extended, or thinly spread, compared to their quantity or volume, a rapid interchange of temperature will take place, (assimulated to mixing), and each of them will acquire the medium temperature in a very short space of time. Now if the two fluids be made to pass each other in opposite directions, through a vessel or apparatus having contiguous passages, so that the temperatures of the liquors may act upon each other, separated by a thin metallic surface, greatly extended, compared to the quantity or volume of the liquor; or in other words, so that two thin sheets or lamina, (as they may be called), one of hot fluid, the other of cold, be made to act upon each others temperature, passing in opposite directions, and the thickness of such sheets or lamina of fluid, do not exceed half an inch, and may be as thin as one sixteenth of an inch, the interchange of temperature will rapidly take place, and with nearly the same effect as if they were mixed together; and if these contiguous passages be of sufficient length, I find, that the hot fluid entering its passage at one end of the apparatus, and the cold fluid entering its passage at the reverse end of the apparatus, there will be very nearly a complete transfusion of heat, and by actual experiment I have found, that wort, or other heated fluid, entering my apparatus at a temperature above 200° Fahr. will pass out at a temperature of 60° Fahr. while the water entering at 56°, will come out at a temperature above 190°; a little heat being necessarily lost by radiation, or the exchange of temperature would he more complete. Having made these general explanatory observations, I proceed to describe my apparatus.” Plate III, figs. I, 2, and 3, represent different forms in which the apparatus is proposed to be made. The two first have zigzag passages, the third, channels running in convolate curves. These channels or passages, are of very small capacity in thickness, but of great length, and of any breadth that may be required according to the quantity of fluid intended to be cooled or heated. 4 Fig. 4, is the section of a portion of the apparatus, (shewn at figs. 1, and 2, upon an enlarged scale, it is made by connecting three sheets of copper or any other thin metallic plates together, leaving parallel spaces between each plate, for the passage of the fluids, represented by the black lines. These spaces are formed by occasionally introducing between the plates, thin straps, ribs, or portions of metal, by which means very thin channels are produced, and through these channels the fluids are intended to be passed, the cold liquor running in one direction, the hot in the reverse direction. Supposing that the passages for the fluids are each one |