If it be fuggefted, that this probofcis may have been produced in a long courfe of generations, by the conftant endeavour of the elephant to thrust out his nofe, (which is the general hypothefis by which it has lately been attempted to account for the forms of animated nature,) I would afk, how was the animal to subsist in the mean time; during the procefs; until this prolongation of fnout were completed? What was to become of the individual, whilft the fpecies was perfecting?

Our business at prefent is, fimply to point out the relation, which this organ bears to the peculiar figure of the animal, to which it belongs. And, herein, all things correfpond. The neceffity of the elephant's probofcis arifes from the shortnefs of his neck; the fhortness of the neck is rendered neceffary by the weight of the head. Were we to enter into an examination of the ftructure and anatomy of the probofcis itself, we should fee in it one of the most curious of all examples of animal mechanism. The difpofition of the ringlets and fibres, for the purpose, firft, of forming a long cartilaginous pipe ; fecondly, of contracting and lengthening that pipe; thirdly, of turning it in every direction at the will of the

animal;

animal; with the fuperaddition, at the end, of a fleshy production, of about the length and thickness of a finger, and performing the office of a finger, so as to pick up a straw from the ground; these properties of the same organ, taken together, exhibit a specimen, not only of defign, (which is attested by the advantage,) but of confummate art, and, as I may fay, of elaborate preparation, in accomplishing that defign.

II. The hook in the wing of a bat, is ftrictly a mechanical, and, also, a compensating contrivance. At the angle of its wing there is a bent claw, exactly in the form of a hook, by which the bat attaches itself to the fides of rocks, caves, and buildings, laying hold of crevices, joinings, chinks, and roughnesses. It hooks itself by this claw; remains fufpended by this hold; takes its flight from this pofition: which operations compenfate for the decrepitude of its legs and feet. Without her hook, the bat would be the most helpless of all animals. She can neither run upon her feet, nor raife herself from the ground. These inabilities are made up to her by the contrivance in her wing: and in placing a claw on that part, the Creator has deviated from the analogy

6

analogy observed in winged animals. A fingular defect required a fingular fubftitute.

III. The crane kind are to live and feek their food amongst the waters; yet, having no web feet, are incapable of swimming. To make up for this deficiency, they are furnished with long legs for wading, or long bills for groping; or ufually with both. This is compenfation. But I think the true reflection upon the present inftance is, how every part of nature is tenanted by appropriate inhabitants. Not only is the furface of deep waters peopled by numerous tribes of birds that swim, but marshes and shallow pools are furnished with hardly less numerous tribes of birds that wade.

IV. The common parrot has, in the structure of its beak, both an inconveniency, and a compenfation for it. When I fpeak of an inconveniency, I have a view to a dilemma which frequently occurs in the works of nature, viz. that the peculiarity of structure by which an organ is made to answer one purpofe, neceffarily unfits it for fome other purpofe. This is the cafe before us. The upper bill of the parrot is fo much hooked, and so much overlaps the lower, that, if, as in other birds,

the

the lower chap alone had motion, the bird could scarcely gape wide enough to receive its food; yet this hook and overlapping of the bill could not be fpared, for it forms the very inftrument by which the bird climbs to fay nothing of the ufe which it makes of it in breaking nuts, and the hard fubftances upon which it feeds. How, therefore, has nature provided for the opening of this occluded mouth? By making the upper chap moveable, as well as the lower. In most birds the upper chap is connected, and makes but, one piece, with the skull; but, in the parrot, the upper chap is joined to the bone of the head by a ftrong membrane, placed on each fide of it, which lifts and depreffes it at pleasure *.

V. The fpider's web is a compenfating contrivance. The fpider lives upon flies, without wings to pursue them; a cafe, one would have thought, of great difficulty, yet provided for; and provided for by a resource, which no ftratagem, no effort of the animal, could have produced, had not both its external and internal ftructure been fpecifically adapted to the operation.

Goldfmith's Nat. Hift. vol. v. p. 274.

VI. In many fpecies of infects the eye is fixed; and confequently without the power of turning the pupil to the object. This great defect is, however, perfectly compenfated; and by a mechanism which we should not suspect. The eye is a multiplying glass; with a lenfe looking in every direction, and catching every object. By which means, although the orb of the eye be stationary, the field of vision is as ample as that of other animals; and is commanded on every fide. When this lattice work was first observed, the multiplicity and minuteness of the furfaces must have added to the surprise of the discovery. Adams tells us, that fourteen hundred of these reticulations have been counted in the two eyes of a drone bee.

In other cafes, the compenfation is effected, by the number and position of the eyes themfelves. The spider has eight eyes, mounted upon different parts of the head, two in front, two in the top of the head, two on each fide. These eyes are without motion; but, by their fituation, fuited to comprehend every view, which the wants or fafety of the animal render it neceffary for it to take.

VII. The