Page:Philosophical Transactions - Volume 001.djvu/271

 the Mouths or Hands of those patients, to whom it may be allow'd, may be potently cool'd, and other such refreshments may be easily procur'd.

4. How far Sal Armoniack, mingl'd with Sand or Earth, and not dissolv'd, but only moistn'd with a little Water sprinkl'd on it, will keep Bottles of Wine or other liquors more coole, than the Earth or that Sand alone will do, I have not yet had opportunity by sufficient trials fully to satisfie my self, and therefore resign that Enquiry to the Curious.

5. For the cooling of Air, and Liquors, to adjust Weather-glasses (to be able to do which, at all times of the year, was one of the chief aimes, that made me bethink my self of this Experiment,) or to give a small quantity of Beer &c. a moderate degree of coolness, it will not be requisite, to employ neer so much as a whole pound of Sal Armoniack at a time. For, you may easily observe by a seal'd Weather-glass, that a very few ounces, well pouder'd and nimbly dissolv'd in, about 4. times the weight of Water, will serve well enough for many purposes.

6, And that you may the less, scruple at this, I shall tell you, that even before and after Midsummer, l have found the Cold producible by our Experiment to be considerable and useful for refrigerating of Drinks, &c. but if the Sal Armoniack be of the fittest sort (for I intimated above, that I suspected, 'tis not equally good) and if the season of the year do make no disadvantagious difference, the degree of Cold, that may be produced by no more than one pound (if not by less) of Sal Armoniack, may, within its own Sphere of Activity, be much more vehement, than, I presume, you yet imagine, and may afford us excellent Standards to adjust seal'd Weather-glasses by; and for several other purposes. For I remember that in the Spring, about the end of March, or beginning of April, I was able with one pound of Sal Armoniack, and a requisite proportion of Water, to produce at degree of Cold much greater, than was necessary the preceding Winter, to make it frosty Weather abroad; nay I was able to produce real Ice in a space of time, almost incredibly short. To confirm which particulars, because they will probably seem strange to you, I will here annex the Transcript of an entry, that I find in a Note book of the Phænomena and success of one of those Experiments; as I then tryed it; though I should be asham'd to expose to your perusal a thing so rudely pen'd; if I did not hope, you would consider, that 'twas hastily written onely for my own Remembrance. And that you may not stop at any thing in the immediately annext Note, or the two, that follow, it will be requisite to premise this Account of the seal'd Thermoscope; (which was a good one) wherewith these Observations were made; That the length of the Cylindrical pipe was 16. Inches, the Ball, about the bigness of a somewhat large Walnut, and the Cavity of the Pipe by guess about an eight or ninth part of an inch Diameter.

The First Experiment is thus registred. March the 27th, in the Seal'd Weather glass, when first put into the Water, the tincted Spirit rested at 8 inches: being suffered to stay there a good while, and now and then stirr'd to and fro in the Water; it descended at length a little beneath 7 inches; then the Sal Armoniack being put in, within about a quarter of an hour or at little more it descended to 2 inches, but before that time, in half a Rh