Page:Proceedings of the Royal Society of London Vol 1.djvu/49

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perception of these explosions;—and lastly, that the hearing will be strongly affected by introducing into the ears two probes, the opposite extremities of which are connected with the two ends of the apparatus. No effect has as yet been produced upon the sense of smell by. this machine, which is ascribed to the circumstance of the electric effluvia not being expanded in and conveyed by the air, which it is thought is the proper vehicle for exciting sensations in the olfactory nerves.

At the close of the paper the author points out the striking analogy there is between this apparatus and the electric organs of the torpedo and electric eel, which are known to consist of membranaceous columns filled from one end to the other with a great number of laminae or pellicles, floating in some liquid which flows into and fills the cavity. These laminae cannot be supposed to be excited by friction, nor are they likely to be of an insulating nature; and hence these organs cannot be compared either to the Leyden phial, the electrophore, the condenser, or any other machine capable of being excited by friction. As yet, therefore, they can only be said to bear a resemblance to the apparatus described in this paper. The effects hitherto known of this apparatus, and those which there is every reason to expect will be discovered hereafter, are likely, it is thought, to Open a vast field for reflections and inquiries, not only curious but also interesting, particularly to the anatomist, the physiologist, and the physician.

Some Observations on the Head of the Ornithorhynchus paradoxus.By Everard Home, Esq. F.R.S.Read July 3, 1800.[Phil. Trans. 1800, p. 432.]

We learn from this communication that the beak of this singular animal, which on a cursory examination was thought to be exactly similar to that of the Duck, and calculated for the same purposes, is in fact materially different from it; and that, so far from being the mouth of the animal, as had been imagined, it is only a part added to the mouth, and projecting beyond it. This mouth has two grinding teeth on each side, both in the upper and lower jaw; they are without fangs, and may be considered as bony protuberances. Instead of incisor teeth, the nasal and palate bones are continued forwards, so as to support the upper portion of the beak; while the two under jaws are likewise continued forwards in the shape of two thin plates of bone, forming the central part of the under portion of the beak. The tongue is very short, and when extended can be projected into the bill scarcely one quarter of its length.

The organ of smell in this animal differs from that of quadrupeds in general, as well as of birds. The nostrils are nearly at the end of the beak, while the turbinated bones are situated in the skull, as in other quadrupeds; by which means there are two cavities the whole length of the beak superadded to this organ. The nerves which supply this organ are very large in proportion to the size of the animal.