vegetable kingdom that, though cold, abounds with spirit; for camphire, which is spirituous, yet performs the actions of cold, refrigerates only by accident; viz. by its tenuity, without acrimony, and by promoting perspirations in inflammations.

In the congelation and freezing of liquors, lately introduced by the application of snow and ice without-side the containing vessel, nitre is used as an ingredient; and doubtless both excites and strengthens the freezing power. It is true, common bay-salt is used for the same purpose; but this rather actuates the cold of the snow or ice, than gives a coldness of itself. I have been told that in the hotter regions, where no snow falls, congelation has been performed by nitre alone: though this is not hitherto verified.*

But

Gunpowder, whereof nitre makes the principal ingredient, is reported, when drank, to in

*I suppose this is meant of the coolness which nitre communicates to water during the time it continues dissolving therein. But does not the act of congelation require salarmonic instead of nitre; and a second or third repetition of the solution, after both the salt and the water have remained in the former solutions, to acquire their degrees of cold respectively? For scarce any salt will produce ice upon being barely dissolved in the water of a warm climate; unless the water be considerably cooled before. See Sylva Sylvarum, under the articles, Cold, Coolness, and Heat.

spire courage, and to be frequently taken by sailors and soldiers before battle; as opium is by the Turks.

Nitre is successfully given in calentures, and pestilential fevers; to suppress and cool their destructive heats.

It is very manifest from gunpowder, that nitre has a great aversion to flame; whence proceeds that surprising ventosity and explosion.

Nitre is found to be, as it were the spirit of the earth for it is certain that any clean earth, unmixed with nitrious bodies thrown on heaps, and kept covered and screened from the sun, so as to afford no vegetables, will copiously collect nitre: whence it is manifest, that the native spirit of nitre is of a lower rank than the spirit of animals, or even of vegetables.

Animals that drink nitrious water grow manifestly fat; which is a sign of coldness in nitre.*

Land is best improved by nitrious bodies; and all manure is nitrious; which shews there is a spirit in nitre.

From all which it is plain, that the human spirits may be cooled and condensed by the native spirit of nitre; and at the same time rendered more dense and less consuming: and therefore,

*Where are these nitrious waters found? or what is here properly meant by nitrious waters ?

as strong wines, spices and the like inflame the spirits and shorten life; so nitre on the other hand, composes and condenses them, and conduces to longevity.

Nitre may be used at meals, mixed along with nine parts of table salt; it may also be taken with the breakfast or morning's-draught, from three grains to ten but in what way soever it be moderately used, it is highly conducive to long life.

As opium stands first in virtue for condensing the spirits by flight, and has its less powerful but safer subalterns; which may be taken in larger doses, and with greater frequency; so nitre likewise, which stands first for condensing the spirits by cold, or rather by cooling and refreshing them at once, has its substitutes.

The substitutes for nitre, are those things which yield an odour somewhat earthy; as that of clean and good earth, newly broke or turned up with the plough or spade. Among the principal of these are borage, bugloss, langue de bœuf, burnet, strawberry the fruit and leaf, rasberries, raw cucumbers, raw apples, vine-leaves, vine-buds, and violets.

Next to these come such as have a certain greenness or rawness of smell, with some tendency to warmth, yet not without a cooling property: as balm, green lemons, green oranges, rose-wa

ter; the pale, the damask, the red, and the musk

rose.

Let it be observed, that the substitutes for nitre, generally answer the intention better in a crude state, than after having felt the fire; because the cooling spirit is dissipated by heat: whence they are best taken, either infused in liquor, or without preparation.

As the spirits are somewhat condensed by the substitutes for opium, so likewise are they by the odour of the substitutes for nitre; so the smell of fresh and clean earth, received either by following the plough, or by digging or by weeding in the garden, excellently composes the spirits; which are likewise finely refreshed by the scent of the leaves that toward the end of autumn fall in the woods and hedges; but above all by the breath of a dying strawberry-bed; and the odour of violets, wall-flowers, bean-blossoms, sweet-briar, and honey-suckles, has a like effect whilst they are growing. And I knew a certain nobleman of a great age, who, as soon as he awaked in the morning, had a piece of fresh earth every day brought him, in order to receive its odour.

And no doubt but the blood being cooled and tempered by such cold plants as endive, succory, purslain, &c. might consequently cool the spirits; but this is a slow and indirect way; where

as vapours operate immediately. And so much for the condensation of the spirits by cold.

3. The third kind of condensation is by appeasing the spirits. Now the spirits are appeased by such things as prove grateful and acceptable to them, without exciting or calling them out too much; but rather incline them to complacency and self-satisfaction, and to keep themselves within their own sphere. But the particulars of this enquiry are already satisfied by what is above delivered upon the substitutes for opium and nitre.

4. And for the fourth kind of condensation; viz. by quelling the too great vigour, and checking the impetuosity of the spirits, we shall speak to it below, when we come to enquire into their motions. So that having already spoke to their condensation, which regards the substance of them; we next proceed to their degree of heat.

It was before observed, that the heat of the spirits should be neither great nor consuming; but such as rather fits them to prey upon the hard resisting parts, than to carry off the light and fine ones.

Spices, wine, and spirituous liquors must be guarded against, and used with great moderation, and with intervals of abstinence. The same caution reaches to thyme, marjoram, pennyroyal, and all hot and inflammatory plants,