39-4 Scientific Intelligence. 
paper on the Comparative Anatomy of the Eye, lately commu- 
nicated to the Royal Society of Edinburgh. ei I observed a 
very singular fact in Africa, which first awakened my suspicions 
relative to the defective vision of the horse. In that country we 
were forced, from a deficiency of pasturage, to allow our horses 
to graze at perfect liberty on the open desarts, and they, so si- 
tuated, seemed to acquire many of the habits which the animal 
would probably possess in a perfectly wild state. They grazed 
generally in small troops, to which an entire horse, or one of the 
boldest of the geldings, seemed to serve as protector ; on the ap- 
proach of strangers, the troop immediately collected into a cir- 
cle, and remained so until the horse appointed to watch over the 
general safety had ascertained whether or not danger was to be 
apprehended, by a nearer approach of the object suspected. On 
one occasion, having gone into the fields with a few friends, of 
whom one was dressed in a morning gown, and, coming unex- 
pectedly on the troop of horses, they were observed to collect im- 
mediately into a circle, and to detach one of their number, with 
a view to ascertain the nature of the very unusual appearance, 
which they evidently saw but indistinctly, though scarcely three 
quarters of a mile removed from the place wher<^ we stood. It 
was now I remarked, with some surprise, that the horse did not, 
during the very long and circuitous course, approach much nearer 
us, but made hastily for that situation in which we should be 
placed between him and the quarter from whence the wind 
blew ; thus evidently employing the organ of smell in preference 
to that of sight.” 
ACOUSTICS. 
II. On the Polarisation of Sound . — The following curious 
facts, which are considered to prove the Polarisation of Sound, 
are given by Mr Wheatstone, in the Annals of Philosophy, 
No. xxxii. p. 87. 
« I connected,” says he, cc a tuning fork with one extremity of a 
straight conducting rod, the other end of which communicated 
with a sounding-board ; on causing the tuning fork to sound, the 
vibrations w T ere powerfully transmitted, but in gradually bending 
the rod, the sound progressively decreased, and was scarcely 
perceptible when the angle was a right one. As the angle was 
made more acute, the phenomena were produced in an inverted 
