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cundated, soon acquires a hard shell, no otherwise than a husky fruit, or seed, is detached from its pedicle, and is extruded to answer the natural ends, and for further

propagation in due time ; and that we may not forget any part of our analogy, we must observe further, that, after such feecundation, as we have mentioned, is completed, the ova of the oviparous kinds of animalş, and the ova, or seeds of vegetables, have the same necessity for a certain portion of heat to assist their motion and growth, without which they cannot be put in motion, nor be capable of receiving nourishment; nor consequently can they grow, but must inevitably perish; and when an egg is in a state of incubation or other artificial heat, in order to the propagation of the animal contained in it, the motion is no sooner begun by the heat, in the organization, than the nutritious parts begin by degrees to be conveyed to it by the umbilical vesels, and fo continue, till the whole is taken in by the animal. The fame is the case in every feed fowed in the ground; finer nutritious parts of the seed are conveyed to the little organization, till it has exhausted them, whereby it becomes capable of farther nourishment, as we shall explain it hereafter, when we come to speak of the analogy of the fluids in animals and vegetables.

« All these observations make it evident, beyond contradi&tion, that a refined fluid, from the fenrinal matter of the male, impregnates the organization in the ovum in the female of every animal ; mingles with the fubtile Auids contained in it, and promotes its growth and progress ; so in vegetables, the refined part of that pulpy fluid, thrown out from the globules of farina, also mixes with the juices of, and impregnates the little organization in, the seed of every plant. Now by this admixtion and combination of these refined fruids, which we have often called an effluvium in the male parts, there is an immediate alteration produced that was not existent in the ovum or seed before ; for the innate juices of the organization has qualities peculiar to itself, as to colour, tafte, smell, &c. be its quantity never so small; so no one can in the least doubt, but the impregnating effluvium of the male parts of animals and vegetables has its own peculiar qualities, as to eclour, tafte, smeli, &c. Now, therefore, it can be no difficult matter to conceive how the congress of a black man with a white woman, or vice versa, should propagate a proles of a colour between both; the common experiment of mixing what we call a flesh-colour and black, in certain proportions, will produce a tawney, and in great measure also influence its form, as it grows. And thus in vegetables, if the farina of one

species

species of plant or tree should reach the flower of another, and fæcundate the ovarium, the colour of the future flower and fruit would be variegated, and the form of the fruit a great deal influenced too.'

Our author takes notice, in this place, of the benignity of the Divine BEING, in having done every thing that might favour the propagation of the human race; for he observes, that tho' different species of men and women : sometimes meet, and copulate, there is such an agreement between the refined parts of the feminal matter of the male and the innate jucies of the organization of the female, that there is nothing in their commixion which can prevent the proles from being capable of further propagation, with any other different species of the human race. He likewise endeavours to account for a phenomenon, which was never, that we know of, accounted for before. When different Species of animals copulate, as for example, a male ass and a mare, their proles cannot produce another proles of any kind : the reason of this, he tell us, is, that the impregnating efluvia, the seminal matter of the mule are so much degenerated, by the former unnatural mixtures of the parents, from any

hoo mogeneity with the particles of the innate juices of the organization in the ovum of its female, or any other whatsoever; that, instead of that agreement that naturally happens in the fæcundation upon the coit of homogeneous animals, the access of those effluvia, in such as are heterogeneous, either utterly destroys the organization, or they have not the proper qualities for promoting any further propagation, and so leave the ova unimpregnated, and consequently incapable of ever coming to any thing.

In the third chapter, he treats of three kinds of organizations, which ferve to the propagation and other advantages of animals and vegetables, viz. the primary, the secondary and the subordinate, organizations. As animals and vegetables are first propagated from eggs, each containing a perfect organization of its own species, he calls this a primary organi. zation. The secondary organizations are those implications of fibres placed in other parts of the plant or animal, and which are capable of producing their species, as well as the first or primary organizations: and the subordinate are such organizations as are placed in certain parts, as at the base of a peculiar limb, &c. to serve occasionally for the use of the animal who possefles them. Of this last kind are the teeth, the nails and hoofs, the hairs and feathers of animals.

• In the larger animals, says he, one complete organizatiou is sufficient to perfect the whole; for animal substances

are

are naturally emollient and flexible, and consequently capable of explication and dilatation, from its beginning to the perfect state of the animal, without any necessity for a fecondary organization ; but in vegetables there is need of divers secondary organizations, whose fibres are more rigid, and of a harder nature, and therefore incapable of being explicated to so great a degree of extension, as many trees and plants acquire.

In all trees or plants the primary organization being, as we have before observed, in the seed or ovum, the first explication is completed in the first shoot; because, when this is done, then the secondary organization, which consists of the rudiments of the first ramification, deposited and growing at the end of this shoot in the most convenient place, has room for its explication. And, when each ramification is explicated to its proper length, it may to the succeeding ones it contains, in like manner, be accounted another shoot; and so on to the extremities of every ramification, as long as the tree or plant can grow. Hence every branch coming out of another, proceeds from a perfect organization, deposited at the upper end of the first, where it occasionally appears; and hence every branch is capable of growing into a persect tree or plant, like the parent of the ovum, which produced it first; so that, to sum it up, the first shoot of a tree or plant grows on to form the trunk, sending off other ramifications from its organizations, as it rises; whilft each ramification goes to form a limb or arm, as it spreads ; sending off other ramifications, from its or. ganizations, and so on, to the utmost extremity and growth.

. And when we see some species of trees or plants rise very high and slender, without leaf or branch, it can be fo only, because no part of them have such secondary organizations, in the way to produce them ; so that the ala of every leaf contains an organization too, from whence a tree or plant may be propagated, which daily experience will shew. Every one who is conversant in country affairs, knows that to cut an ozier in pieces, and plant them, they will produce trees; and so will cuts, of gooseberry and currant-trees ; and I am now pretty sure tender cuts of any others will do the same. I have tried several at different times, which I cut and planted, taking an account of the number of these organizations in each piece, and always found that the sproutings were from these organizations; and, on the other hand, have often experienced that no piece without an organization ever grew, but rotted away. I have planted cuttings

and

and flips of various plants, and, from many repeated observations and experiments, found that no part produced a bud or germ but these organizations.'

In this chapter, and indeed in many other parts of his work, our ingenious author has interspersed several judicious and pious reflections on the wisdom and goodness of the great former and father of the universe ; setting herein an excellent example to all who study the works of nature, of proposing to themselves, as one great end of all their enquiries, the cultivation of high and honourable apprehenfions of the divine perfections.

In the fourth chapter he confiders the analogy between the Auids of animals and vegetables, and endeavours to explain the secretions in both. As in the general organization of animals and vegetables, says he, there is this indisputable analogy; so it also wonderfully holds in the fluids that feverally belong to them. And, to conceive it well, we need only take a view of any particular seed, and we shall find treasured up in it not only the organization I have been speaking of, but also its native or innate juices ; that is, a certain quantity of every individual Auid, which is afterwards to be found in larger quantities, in the tree or plant that arises from the feed, deposited there, each in its peculiar vessel, ready to be encreased and secreted in its due order, upon the accretion of the organization, and capable of being joined by similar particles, arising from the general nutritious juices in the earth, their natural matrix.

He illustrates this by some observations made on different seeds, and then proceeds thus. « We must then consider the nutritive juices produced by the mutual concurrence of the air, water, and the earth, the natural matrix of the vegetable kingdom, to be an heterogeneous fluid, composed of all the species of juices, which are found in every part of all trees or plants whatsoever; and this must be looked upon as the general magazine of provision for all those vegetables which are nourished by them, in whatsoever climate they grow; and then we must look upon the feed or ovum to have treasured up in it, originally, an innate sufficient quantity of every one of the particular juices of its parent, each in its own peculiar vessel, proportioned to the capacity of its receptacle, whether it be a primary or secondary organization of tree or plant ; or in other words, whether it be the seed or bud. And, next to this, we may observe, as in the reveral instances above mentioned, a congeries of substances omprehended in the parenchyma of every seed, the very

fame

same with those different innate juices natural to the little organization, which are contained in this feed along with it, and inclosed in the same covering, intended, as the first fupply, to be received for nutrition by the tender parts of the organization ; until it is capable of receiving, secreting, and being nourished by the proper juices out of the general fluid mentioned, always sufficiently abundant in this natural matrix, the earth.

But now we are to consider the manner of the fecretion of these peculiar juices, into the several vessels in the little organizations; which probably may be in the following inanner: as soon as the seed is put into its natural matrix, the earth, its case or covering is soon burst open, by the access of moisture and heat, which, gradually, first dirsolve the several nutritious juices supplied by the parenchyma, and put them in motion ; whilft, at the same time, the organization is released from the pressure of this parenchyma by degrees; and now the absorbent vessels or radiculi of the organization, being touched on all sides by the Auids of the diffolved parenchyma, receive it, and carry it up to the little secretory vessels, none of which will admit any other particles of the general Auid to pass into them, but such as are similar to that which it contains already ; they alone being capable of being attracted by their kindred particles; and, as the quantity is thus increased within, the attraction will grow stronger, and the explication of the plant be more accelerated, till the organization arrives to its full growth; each part carrying on its particular business; some attracting and separating to themselves, out of this general fluid that is driven up, the juices of the leaf; fome of the guin; fome of the flower; some of the fruit; and so on, till the full completion of the whole, whether of tree or plant; according to their peculiar natures and necessities; for when the general Auid is carried to the secretory vessels, and each has separated and attracted its own particles, the others, which are heterogeneous to these, pass over these orifices, and are attracted in their turn, into those wherein their innate kindred juces lay before, and by no others; the roots always receiving the general mass of fluids for those purposes.

The juices attracted into a tree or plant, being the general mals, as is observed before, which is compofed of particles of innumerable various fubftances, it is no wonder, after every part

of

any tree or plant has attracted its kindred particles, that the superfluous juices should be carried off by

perspiration,

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