having known it cure a very bad anarsaca in a person whose thirst, though very extraordinary, was in a short time removed by the drinking of tar-water.

7. The usefulness of this medicine in inflammatory cases is evident, from what has been already observed. (Sect. 5.) And yet some perhaps may suspect that, as the tar itself is sulphureous, tar-water must be of a hot and inflaming nature. But it is to be noted that all balsams contain an acid spirit, which is in truth a volatile salt. Water is a menstruum that dissolves all sorts of salts, and draws them from their subjects. Tar, therefore, being a balsam, its salutary acid is extracted by water; which yet is incapable of dissolving its gross resinous parts, whose proper menstruum is spirit of wine. Therefore tar-water, not being impregnated with resin, may be safely used in inflammatory cases: and in fact it hath been found an admirable febrifuge, at once the safest cooler and cordial.

8. The volatile salts separated by infusion from tar, may be supposed to contain its specific virtues. Mr. Boyle and other later chemists are agreed that fixed salts are much the same in all bodies. But it is well known that volatile salts do greatly differ, and the easier they are separated from the subject, the more do they possess of its specific qualities. Now, the most easy separation is by the infusion of tar in cold water, which to smell and taste shewing itself well impregnated may be presumed to extract and retain the most pure volatile and active particles of that vegetable balsam.

9. Tar was by the ancients esteemed good against poisons, ulcers, the bites of venomous creatures; also for phthisical, scrofulous, paralytic, and asthmatic persons. But the method of rendering it an inoffensive medicine and agreeable to the stomach by extracting its virtues in cold water, was unknown to them. The leaves and tender tops of pine and fir are in our times used for diet drinks, and allowed to be antiscorbutic and diuretic. But the most elaborate juice, salt, and spirit of these evergreens, are to be found in tar; whose virtues extend not to animals alone, but also to vegetables. Mr. Evelyn, in his treatise on "Forest Trees," observes with wonder, that stems of trees, smeared over with tar, are pre

served thereby from being hurt by the invenomed teeth of goats, and other injuries, while every other thing of an unctuous nature is highly prejudicial to them.

10. It seems that tar and turpentine may be had, more or less, from all sorts of pines and firs whatsoever; and that the native spirits and essential salts of those vegetables are the same in turpentine and common tar. In effect, this vulgar tar, which cheapness and plenty may have rendered contemptible, appears to be an excellent balsam, containing the virtues of most other balsams; which it easily imparts to water, and by that means readily and inoffensively insinuates them into the habit of the body.

11. The resinous exudations of pines and firs are an important branch of the materia medica, and not only useful in the prescriptions of physicians, but have been also thought otherwise conducive to health. Pliny tells us that wines in the time of the old Romans were medicated with pitch and resin; and Jonstonus in his "Dendrographia" observes, that it is wholesome to walk in groves of pine-trees, which impregnate the air with balsamic particles. That all turpentines and resins are good for the lungs, against gravel also and obstructions, is no secret. And that the medicinal properties of those drugs are found in tar-water, without heating the blood, or disordering the stomach, is confirmed by experience; and particularly, that phthisical and asthmatic persons receive speedy and great relief from the use of it.

12. Balsams, as all unctuous and oily medicines, create a nauseating in the stomach. They cannot therefore be taken in substance so much or so long as to produce all those salutary effects, which, if thoroughly mixed with the blood and juices, they would be capable of producing. It must therefore be a thing of great benefit to be able to introduce any requisite quantity of their volatile parts into the finest ducts and capillaries, so as not to offend the stomach, but, on the contrary, to comfort and strengthen it in a great degree.

13. According to Pliny, liquid pitch (as he calls it) or tar was obtained by setting fire to billets of old fat pines or firs. The first running was tar, the latter or thicker running was

pitch. Theophrastus is more particular: he tells us the Macedonians made huge heaps of the cloven trunks of those trees, wherein the billets were placed erect beside each other: that such heaps or piles of wood were sometimes a hundred and eighty cubits round, and sixty or even a hundred high: and that, having covered them with sods of earth to prevent the flame from bursting forth (in which case the tar was lost), they set on fire those huge heaps of pine or fir, letting the tar and pitch run out in a channel.

14. Pliny saith, it was customary for the ancients to hold fleeces of wool over the steam of boiling tar, and squeeze the moisture from them, which watery substance was called pissinum. Ray will have this to be the same with the pisselæum of the ancients; but Hardouin, in his notes on Pliny, thinks the pisselæum to have been produced from the cones of cedars. What use they made of these liquors anciently I know not; but it may be presumed they were used in medicine, though at present, for aught I can find, they are not used at all.

15. From the manner of procuring tar (sect. 13) it plainly appears to be a natural production, lodged in the vessels of the tree, whence it is only freed and let loose (not made) by burning. If we may believe Pliny, the first running or tar was called cedrium, and was of such efficacy to preserve from putrefaction that in Egypt they embalmed dead bodies with it. And to this he ascribes their mummies continuing uncorrupted for so many ages.

16. Some modern writers inform us that tar flows from the trunks of pines and firs, when they are very old, through incisions made in the bark near the root; that pitch is tar inspissated; and both are the oil of the tree grown thick and ripened with age and sun. The trees, like old men, being unable to perspire, and their secretory ducts obstructed, they are, as one may say, choked and stuffed with their own juice.

17. The method used by our Colonies in America for making tar and pitch is in effect the same with that of the ancient Macedonians; as appears from the account given in the "Philosophical Transactions." And the relation of Leo Africanus, who describes, as an eye-witness, the making of tar on Mount Atlas, agrees in substance with the methods

used by the Macedonians of old, and the people of New England at this day.

18. Jonstonus, in his "Dendrographia," is of opinion, that pitch was anciently made of cedar, as well as of the pine and fir grown old and oily. It should seem indeed that one and the same word was used by the ancients in a large sense, so as to comprehend the juices issuing from all those trees. Tar and all sorts of exudations from evergreens are, in a general acceptation, included under the name resin. Hard coarse resin or dry pitch is made from tar, by letting it blaze till the moisture is spent. Liquid resin is properly an oily viscid juice oozing from the bark of evergreen trees, either spontaneously or by incision. It is thought to be the oil of the bark inspissated by the sun. As it issues from the tree it is liquid, but becomes dry and hard, being condensed by the sun or by fire.

19. According to Theophrastus, resin was obtained by stripping off the bark from pines, and by incisions made in the silver fir and the pitch pine. The inhabitants of Mount Ida, he tells us, stripped the trunk of the pine on the sunny side two or three cubits from the ground. He observes that a good pine might be made to yield resin every year; an indifferent every other year; and the weaker trees once in three years; and that three runnings were as much as a tree could bear. It is remarked by the same author that a pine doth not at once produce fruit and resin, but the former only in its youth, the latter in its old age.

use.

20. Turpentine is a fine resin. Four kinds of this are in The turpentine of Chios or Cyprus, which flows from the turpentine tree: the Venice turpentine, which is got by piercing the larch tree: the Strasburgh turpentine, which Mr. Ray informs us is procured from the knots of the silver fir; it is fragrant and grows yellow with age: the fourth kind is common turpentine, neither transparent nor so liquid as the former; and this Mr. Ray taketh to flow from the mountain pine. All these turpentines are useful in the same intentions. Theophrastus saith, the best resin or turpentine is got from the terebinthus growing in Syria and some of the Greek islands. The next best from the silver fir and pitch pine.

21. Turpentine is on all hands allowed to have great

medicinal virtues. Tar and its infusion contain those virtues. Tar-water is extremely pectoral and restorative; and, if I may judge from what experience I have had, it possesseth the most valuable qualities ascribed to the several balsams of Peru, of Tolu, of Capivi, and even to the balm of Gilead, such is its virtue in asthmas and pleurisies, in obstructions and ulcerous erosions of the inward parts. Tar in substance mixed with honey I have found an excellent medicine for coughs. Balsams, as hath been already observed, are apt to offend the stomach, but tar-water may be taken without offending the stomach. For the strengthening whereof it is the best medicine I have ever tried.

22. The folly of man rateth things by their scarceness, but Providence hath made the most useful things most common. Among those liquid oily extracts from trees and shrubs which are termed balsams, and valued for medicinal virtues, tar may hold its place as a most valuable balsam. Its fragrancy sheweth that it is possessed of active qualities, and its oiliness that it is fitted to retain them. This excellent balsam may be purchased for a penny a pound, whereas the balsam of Judea, when most plenty, was sold on the very spot that produced it, for double its weight in silver, if we may credit Pliny; who also informs us, that the best balsam of Judea flowed only from the bark, and that it was adulterated with resin and oil of turpentine. Now, comparing the virtues I have experienced in tar with those I find ascribed to the precious balm of Judea, of Gilead, or of Mecha, (as it is diversely called), I am of opinion that the latter is not a medicine of more value or efficacy than the former.

23. Pliny supposed amber to be a resin, and to distil from some species of pine-which he gathered from its smell. Nevertheless, its being dug out of the earth shews it to be a fossil, though of a very different kind from other fossils. But thus much is certain, that the medicinal virtues of amber are to be found in the balsamic juices of pines and firs. Particularly the virtues of the most valuable preparation, I mean salt of amber, are in a great degree answered by tar-water, as a detergent, diaphoretic, and diuretic.

24. There is, as hath been already observed, more or less oil and balsam in all evergreen trees, which retains the acid