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 Judæa, 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."

The learned Bishop then cites the opinion of Theophrastus, that trees which grow on mountains exposed to the sun or north wind, produce much thinner, sweeter, and better-scented tar, than those growing on plains, and adds, that he himself had found the same difference between the tar that comes from Norway, and that made in low and swampy countries. He considers the anatomy of trees, remarking that Doctor Grew, and others, who have examined their structure by microscopes, have discovered there, an admirable variety of fine capillary tubes and vessels, fitted for the several purposes of imbibing or attracting proper nourishment, and distributing it through every part of the vegetable. They have ducts for the conveyance of air, answering to the tracheæ in animals, lacteals, arteries, and veins. They feed, digest, respire, perspire, and generate, and are furnished with secretory and exhaling vessels for carrying off execrementitious parts. The alimentary juice taken into the lacteals of animals, or vegetables, consists of oily, aqueous, and saline particles, and is partly exhaled into the air; and that which remains is, by the economy of the plant, and the action of the sun, strained and concocted into an inspissated oil or balsam, which, weeping or sweating through the bark, hardens into resin. This secretion is most copious in pines and firs, whose oil being in greater quantity, and more tenacious of the acid spirit, or vegetable soul, as Berkeley calls it, undergoes the action of the sun, by which it is exalted and enriched, so as to become a most noble medicine. "Such," he says, "is the last product of a tree perfectly maturated by time and sun."

"It should seem, that the forms, souls, or principles of vegetable life, subsist in the light or solar emanation, which, in respect of the macrocosm, is what the animal spirit is to the microcosm; the interior tegument, the subtle instrument and vehicle of power. No wonder, then, that the ens primum, or scintilla spirituosa, as it is called, of plants, should be a thing so fine and fugacious, as to escape our nicest search. It is evident, that nature, at the sun's approach, vegetates; and languishes at his recess; this terrestrial globe seeming only a matrix, disposed and prepared to receive life from his light; whence Homer, in his hymns, styleth earth the wife of heaven, aλox ougavỡ ἀσερόεντος.

"The luminous spirit, which is the form, or life, of a plant, from whence its differences and properties flow, is somewhat extremely

volatile. It is not the oil, but a thing more subtle, whereof oil is the vehicle, which retains it from flying off, and is lodged in several parts of the plant, particularly in the cells of the bark, and in the seeds. This oil, purified and exalted by the organical powers of the plant, and agitated by warmth, becomes a proper receptacle of the spirit ; part of which spirit exhales through the leaves and flowers, and part is arrested by this unctuous humour that detains it in the plant. It is to be noted, this essential oil animated, as one may say, with the flavour of the plant, is very different from any spirit that can be procured from the same plant by fermentation.

"Light impregnates air, air impregnates vapour; and this becomes a watery juice by distillation, having risen first in the cold still with a kindly gentle heat. This fragrant vegetable water is possessed of the specific odour and taste of the plant. It is remarked, that distilled oils, added to water, for counterfeiting vegetable water, can never equal it, artificial chemistry falling short of the natural.

"The less violence is used to nature, the better its produce. The juice of olives or grapes, issuing by the lightest pressure, is best. Resins that drop from the branches spontaneously, or ooze upon the slightest incision, are the finest and most fragrant. And infusions are observed to act more strongly than decoctions of plants, the more subtle and volatile salts and spirits, which might be lost or corrupted by the latter, being obtained in their natural state by the former. It is also observed, that the finest, purest, and most volatile part, is that which first ascends in distillation. And, indeed, it should seem, the lightest and most active particles required least force to disengage them from the subject."

The Bishop, unquestionably, "considers the matter too curiously." He proceeds, however, by a chain of closely reasoned propositions, to shew the universality of the uses, to which his medicine is applicable. Its acid has the virtue of that of guaiacum. It is gentle, bland, fine, and volatile. Boerhaave said, that whoever could make myrrh soluble by the human body, had found the secret of prolonging his days. The tendency of tar to resist putrefaction, is as remarkable as that of myrrh; for the ancients used it to embalm and preserve the dead. It is a mild deobstruent, a diaphoretic, a diuretic, and a safe and easy alterative. It strengthens weak fibres, and moistens and softens those that are dry and stiff, thus proving a remedy for both extremes. It is a soap as well as an acid, and, therefore, both unctuous and penetrating; a powerful antiphlogistic and preservative against infection. It is efficacious in all cases, where the costly balsam of Peru is administered ;-in asthmas, nephritic pains, colics, and obstructions. It needs no restraint as to diet, hours, or employment. It acts admirably as a cardiac. The transient cheerfulness excited by distilled spirits, is succeeded by corresponding intervals of depression and melancholy; but the calm tranquillity

promoted by this "water of health," is permanent. It is useful in cramps, spasms of the viscera, and paralytic numbness. Even in gout, the origin of which is admitted to be faulty digestion, and which it is so difficult to cure, because heating remedies aggravate its immediate, and cooling ones its remote, cause;—even in gout, tar-water must be efficacious, because, while its active principles strengthen the digestion, and thereby prevent or abate the following fit, it is not sufficiently heating to do harm, even during the fit.

It would be endless to enumerate the cases in which tarwater is described by the Bishop as remedial, or the various medicines which it supersedes. In the following eloquent passage, he vindicates its utility in those nervous disorders, which, being seated in the mind, belong to a class of maladies "wherein the patient must minister to himself."

"This safe and cheap medicine," he says, "suits all circumstances and all constitutions, operating easily, curing without disturbing, raising the spirits without depressing them, a circumstance that deserves repeated attention, especially in these climates, where strong liquors so fatally and so frequently produce those very distresses they are designed to remedy; and, if I am not misinformed, even among the ladies themselves, who are truly much to be pitied. Their condition of life makes them a prey to imaginary woes, which never fail to grow up in minds unexercised and unemployed. To get rid of these, it is said, there are who betake themselves to distilled spirits. And it is not improbable they are led gradually to the use of those poisons by a certain complaisant pharmacy, too much used in the modern practice, palsy drops, poppy cordial, plague water, and such like, which being, in truth, nothing but drams disguised, yet, coming from the apothecaries, are considered only as medicines.

"The soul of man was supposed, by many ancient sages, to be thrust into the human body as into a prison, of punishment of past offences. But the worst prison is the body of an indolent epicure, whose blood is inflamed by fermented liquors and high sauces, or rendered putrid, sharp, and corrosive, by a stagnation of the animal juices, through sloth and indolence; whose membranes are irritated by pungent salts, whose mind is agitated by painful oscillations of the nervous system, and whose nerves are mutually affected by the irregular passions of his mind. This ferment in the animal economy darkens and confounds the intellect. It produceth vain terrors and vain conceits, and stimulates the soul with mad desires, which, not being natural, nothing in nature can satisfy. No wonder, therefore, there are so many fine persons of both sexes, shining themselves, and shone on by fortune, who are inwardly miserable and sick of life.

"The hardness of stubbed vulgar constitutions renders them insensible of a thousand things, that fret and gall those delicate people, who, as if their skin was peeled off, feel, to the quick, every thing that touches them. The remedy for this exquisite and painful sensibility

is commonly sought from fermented, perhaps from distilled, liquors, which render many lives wretched, that would otherwise have been only ridiculous. The tender nerves and low spirits of such poor creatures would be much relieved by the use of tar- water, which might prolong and cheer their lives. I do, therefore, recommend to them the use of a cordial, not only safe and innocent, but giving health and spirit as surely as other cordials destroy them."

"Studious persons, also, pent up in narrow holes, breathing bad air, and stooping over their books, are much to be pitied. As they are debarred the free use of air and exercise, this I will venture to recommend as the best succedaneum to both. Though it were to be wished, that modern scholars would, like the ancients, meditate and converse more in walks and gardens, and open air, which, upon the whole, would, perhaps, be no hinderance to their learning, and a great advantage to their health. My own sedentary course of life had long since thrown me into an ill habit, attended with many ailments, particularly a nervous cholic, which rendered my life a burthen, and the more so, because my pains were exasperated by exercise. But since the use of tar-water, I find, though not a perfect recovery from my old and rooted illness, yet such a gradual return of health and ease, that I esteem my taking of this medicine the greatest of all temporal blessings, and am convinced that, under Providence, I owe my life to it."

Will it not seem incredible, that the learned Bishop contrives, and by no very abrupt or unpleasing transitions, but by easy and gradual steps, to introduce into his Essay on TarWater, the Newtonian philosophy of light and attraction; the metaphysics of Pythagoras, Plato, and Aristotle; the forms of the Peripatetics; the Aristotelian and Platonic doctrines of the non-existence of corporeal things (the germ of his own theory); the Egyptian Isis and Osiris; the Socratic doctrine opposed to the mechanical or material system; the Trinity of Plato, compared with that of Revelation; and a variety of sound and recondite erudition upon other topics? Having dwelt upon the doctrine of salts, acids, and alkalis, he contemplates air as the common seminary of all vivifying principles. Adopting the ancient hypothesis, he considers it to be a mass of various particles, abraded and sublimated from wet and dry bodies, cohering with particles of æther, the whole permeated by pure æther, or light, or fire, words which the old philosophy used promiscuously. This æther, or pure invisible fire, the most subtle and elastic of all bodies, pervades and expands itself through the whole universe. It is the first natural spring, or mover, from which the air derives its power. Always restless and in motion, it actuates and enlivens the whole visible mass, produces and destroys, and keeps up the perpetual round of generations and corruptions. This æther, or fire, however, is an inferior instrumental cause to the Supreme mind that governs

the mundane system, or macrocosm, with unlimited power, as the human mind, with limited power, directs the microcosm. But, really speaking, no instrumental or mechanical cause can be said to act. Motion itself is only a passion; and the fiery substance is only a means, or instrument, not a real primary efficient. According to the Peripatetics, the fiery ætherial substance contains the form of all inferior beings, and its vital force is vital to all, but diversely received, according to the diversity of the subjects; as all colours are virtually contained in the light, but their distinctions of red, blue, &c. depend on the difference of the objects which it illustrates. The Platonists held, that the intellect resided in a soul, and the soul in an ætherial vehicle. Galen taught, that the soul had for its immediate tegument, or vehicle, a body of æther, or fire, by means of which it moves other bodies, and is, in its turn, affected by them. This interior clothing was supposed to remain upon the soul, not only after death, but after the most perfect purgation, which the Platonists held to be necessary for the cleansing of the soul.

Purumque reliquit

Ætherium sensum atque auræ simplicis ignem.

Accordingly, by the Eastern nations, as well as by the Greeks and Romans, the worship of Vesta, or fire, was retained; Vesta, according to Ovid, being fire.

Nec tu aliud Vestam, quam vivam intellige flammam.

The great principle of Berkeley's philosophy is strongly insisted on in several passages of this dissertation. Natural phænomena, he argues, cannot be accounted for without admitting the immediate presence and action of an incorporeal agent, who connects, moves, and disposes all things according to such rules, and for such purposes, as may seem good to him. All phænomena, to speak truly, are appearances in the soul or mind, and it never has been explained, upon mechanical principles, how external figures and bodies should produce an appearance in the mind. We subjoin an accurate_summary of the Pythagorean and Platonic system, which Berkeley's extensive reading seems to have rendered quite familiar to him.

"The Pythagoreans and Platonists had a notion of the true system of the world. They allowed of mechanical principles, but actuated by soul or mind: they distinguished the primary qualities in bodies from the secondary, making the former to be physical causes, and they understood physical causes in a right sense: they saw the a mind, infinite in power, unextended, invisible, immortal, governed,