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TheInftru. In the same manner he determines the Instrument for it. ment to be employ'd therein ; and upon the
whole concludes, that such a gentle Astion of the Fire, as is always spontaneously present in the Univerfe, being applied to the liquid, and most moveable, Part of a Vegetable Matter, so as to cause little Alteration, and a slight Separation,
must be the first or leading Operation required Vegetables Next follows an Account of the different considered Parts of Vegetables, as divided into Solids with Re- and Fluids, or Vessels and Juices; in order to gard to Cheir velol, lay a Foundation for a due Understanding of andJuices, the first Operation, and the whole Art of Che
mistry: as the Effects thereof upon Vegetable Subjects, he conceives, may be hence clearly perceived ; and the Learner instructed what kind of Separation to expect from chemical Analy
ses, or Resolutions f.
. .And the Doctrine thus deliver'd is afterwards ries from
Doc. summed up in a few Corollaries, as he calls trine of them ; with a direct View to the regular conVegetables. ducting of Processes. The Amount is this :
(1.) That there are great Diversities in the Juices of Vegetables, some of them being much more easily separable by Heat than others; so that too great a degree thereof will often confound or blend them together. (2.) That, consequently, the Chemical Operations upon Vegetables, must be differently suited, or performed upon different Parts thereof, according to the Intention. (3.) That as Vegetables contain Juices of different Colours, in their different Parts, the Ways of extracting these Juices must be differently suited. (4.) That the same is to be observed with regard to their Odours ;, which also reside in particu
lar & Pag. 6. & pag. 7-).
lar Parts. (5.) That the fame is also to be obferved with regard to their Tastes. (6.) Thao the Seasons wherein Plants chiefly abound with the Juices or Parts required, must be carefully observed; as also the Soils wherein they grow and prosper best. (7.) That Plants in the Spring abound with thin, aqueous and faline Juices, and afterwards more with Oil ; so that the fame Operation will procure different Substances from them at different Seasons. (8.) That Chemistry, practised in the exactest Manner, ca'n scarce obtain the Virtues of Vegetables, pure, and perfect; because the Operation constantly mixes the Parts first separated, with those that come after
And thus the preliminary Matters being dispatched, we are led to the first Set of Proceffes, viz. those upon Vegetables; the Author having first recapitulated, and again enforced, the Geometrical Manner he is so fond of, and resovles to proceed in d. ,
This Geometrical Manner we must however obferve, regards no more than the Order wherein the Processes åre placed, one after another ; so as to form a kind of continued Chain, whereof the Processes are the several Links, (tho' frequently broken ;-) but for the Order observed in describing the Processes themselves, it appears no more Geometrical than that of many other Chemical Writers of Processes ; and is perhaps looser than that of Le Fevre, Barchusen, &c. .
But to give the better Idea of the Manner, and Conduct of the Author, it may be proper to single out some one Process, by way of Ex
ample: Pag. gma 12 . Pag. 12, 13,
ample: and none seems more advantageous for him, than the first Process upon Vegetables ; which is designedly fundamental, opens the Scene, leads to the rest, and is one of the most curious Processes of the whole Number.
PROCESS I. « The Distilled Water exhaling, in the Foren of
“ Vapour, from the Plant Rosemary, by the
A PPARAT US,
11. Take Rosemary, fresh gather'd, in its « Prime, in the Morning, with the Dew still 6 hanging upon it, whole, not bruised, and o not having its diftinct Parts mixed by Con. “ tusion; but so contained in its different Ves• sels, as Nature had distributed them in the “ Plant itself, without any other foreign Thing « mixed therewith, except the Dew that sticks “ to it b.
"62. LAY it upon the broad, clean, round
Plate, within the little cylindrical Furnace, « described in Table XVII. Fig. 2. fitted to " the height of two or three Inches ; lay it on 66 gently, without squeezing; and then cover. «o the little Furnace with the large conical Stillas head, made of Pewter; and apply a Glass Re, " ceiver to the Nose,
" 3. With a bright, glowing Coal, that “ yields no Smoke, raise an equable Heat in the “ Furnace, not exceeding eighty-five Degrees “ upon Fahrenheit's Thermometer ; to be kept
i. se up 6 This Period news us something of the Author's faulty Mariner of delivering his Processes, wherein he usually runs in o Tautology, a neediefs Repeticion of Circum, lances, and Particulars no way cllcotiale ;
56 up so long as any Liquor drops from the “ Still-head, into the Receiver. Then taking " away the Plant, a fresh Parcel may be a“ gain successively treated in the same man"ner, till a sufficient quantity of this Water 66 is obtained.
“ 4. Let the procured Liquor stand at rest, « in a clean Glass, exactly stopped, for some " Days, in a cold Place ; when becoming “ limpid, it will have the Smell and Taste of " the Plant. .
The Nature, and Uses, of this Water.
" In this Liquor are contained, 1. the Li( quor of Dew, which consists of its own Parts. “ See Part I. p. 469, 470, 471. that are dif66 ficultly separated from the Plant; but stick “ to it even in drying. Again this Dew, which 66 applies itself externally, contains the liquid s. Parts of Plants, which being digested by the $c Heat of the preceding Day, and exhaling in so the Night, are detained, and with it confti. so cute one external Fluid, that is often clam“ my ; as may appear chiefly in Wax, Manna 66 and Honey.
2. In this Liquor is contained the aqueous 6. Moisture exhaling from the little Veffels of o the Plant examined; which Moisture a
gain consists, for the greatest part, of fim“ple Water ; as appears when it has stood “ long in an open Veffel: where the Smell and “ Taste vanish, and leave an insipid Water be“ hind. Another Part of this Water is the « subtile volatile Substance, which gives the so particular Smell and Taste to the Plant ; “ for this the Senses discover in the Water ;
66 and it is in great measure lost to the Rose66 mary remaining after the Operation. 3. It “ seems also to contain Seeds, or other Corpus, 66 cles, from whence, at a certain Time, a " kind of light, and whitish Weed, or mo“ thery Matter, usually grows in this Water, 66 and hangs suspended in the midst thereof; 66 daily encreasing, and extending its Bulk; tho as it did not appear at first. I have kept these 66 Waters, in separate Vessels, unmov’d, and
close stopped, and found, that after a Year, 66 it began to grow, and then daily increased « more and more, till at last the whole Liquor “ becane ropy with this Mucilage, and grew ss thick and cloudy. Therefore this Water "contains the elementary Water of the Plant, " and the governing Spirit, which is small
in Bulk, but rich in Virtue; and exhibits the “ Smell, and thence the distinct Taste of the 6 Plant. Whence this exhaling Water is the “ Vehicle of that Spirit which exhibits b the * particular Virtue of the Plant, in an ex“ tremely small, subtile, highly volatile, and “therefore easily feparable Subitance ; leaving “the Body of the Plant exhausted in this re66 spect. And hence; therefore, proceeds the « Virtue of these Waters in Medicine; which “ principally depends upon this Governing Spi"rit. For this being in many Plants endow " with a sharp Mobility , affects the Nerves, $ raises the Spirits, and thence helps their In$ activity. But besides this common Princi“ple of Action, it has another that is peculiar, $singular, and wonderfully efficacicus. This “ Paracelsus, in his Language, calls the ap
." propriated spiritus Rector. b Exprimit, Açși Mobilitate,