Feb. 27, 1873) — 
the present purpose to inquire), 
hearing, smell, and taste, 
and intermittently, 
the same things. 
while all other sensations, as of 
come before us only discontinuously 
not being had from all things nor always from 
But in a dog’s experience touch cannot possi- 
bly co-operate with sight as it regularly does in ours. The organ 
of effective touch in man—touch that gets associated with vision 
—is in the last resort the hand, conbining mobility and _sensi- 
_ tiveness in the highest degree ; and the doz has no hand. Its 
mobile limbs are not sensitive at the extremities, and, though it 
has sensitive lips, these, having no such active mobility as the 
human hand has, are extremely limited in the scope of their ap- 
prehension. Its touch being thus defective, wha: is there then 
in the dog to play second to sight, which as leader needs support, 
were it only because there is not always light tosee with? Smell, 
I cannot but think, seeing that, while the organ is incontestably 
acute, it has the great advantage over the tactile surface of the 
lips, of receiving impressions from things already at a distance, 
_ If we only suppose—what the facts make very hk-ly—that the 
dog’s smell is acute enough to have som= sen-ation from all 
ies without exception, nothing more is wanting to enable a 
psychologist to understand that the dog’s worli may be in the 
main a world of sights and s nells continuous in space. In that 
case a dog conveyed in a basket might by smell alone find its way 
back pretty much as a man blindfolded finds his way by touch 
alone, j 
_ To argue properly so difficult a qu 
letter, and I must be content now, for reasons like those in jicated 
rather than stated above, with giving my adhesion to Mr. 
Wallace’s view—so far at least as dogs are concerned, and to the 
extent that in smell we have a source of explanation for the phe- 
nomena which has never been sufficiently considered. That the 
explanation covers all the facts related even about dogs is more 
than I would assert; and whether it is equally serviceable for 
other animals like cats and horses, concernin z which not less 
wonderful stories are told, is not so clear. Cats, however, seem 
to have very acute smell. What is the truth about the smell of 
horses? G. CruoM RopEertTson 
University College, Feb. 24 
Fiords and Glacial Action 
In Naturg, vol. vii. pp. 94, 95, I find the following :— 
“‘ Poggendorf’s Annalen—A, Helland adduces a large amount 
of evidence to show that the fiords in Norway have been formed 
by glacial action.” 
It appears an obvious remark, and yet I have not met with it, 
at fiords are chiefly found in those coasts where from the 
graphical conditions there must have been the most glacial 
action. The most favourable condition; for glacial action are 
vidently those of a mountainous coast ina high and therefore 
cold latitude, fronting the rain and snow-laden west winds of 
the higher latitudes as they blow in from the ocean. These 
Conditions are fulfilled in the highest degree by the coasts of 
Norway and Western Scotland: the western coast of North 
America from Vancouver’s Island northwards 3 and the western 
t of South America from Chile southwards; and these 
Coasts are accordingly more cut up into fiords than any others 
in the world. 
_ The western coast of America along the enormously long line 
from Vancouver's Islard to Chiloe is one of the most unbroken 
nthe world. It is significant that the change in the coast at 
Chiloe from an unbroken one to one very much broken into 
2stion is impossible ia a short 
8, according to Mrs. Someryille’s ‘‘ Physical G-ogriphy.” 
the third south of it, 
About 33° S. (near Valparaiso) . 12,780 feet 
OE Or a aes 7,960 ,, 
53° (Strait of Magellan) . 3,390 ,, 
_ Although the height of the snow-line depends chiefly on Iati- 
tude, it is sensibly influenced by the aspect of the mountains 
pecting the rain and snow-bearing winds. The best instance 
f this is probably that of the Himalayas, where, according to 
\ Somerville (page 314), the heizht of the. snow-line is 
620 feet on the no.th .side, and only 12,980 on the south. 
ee Bet es eh ee fer 2 
ae oi 
Fs eal , i 
NATURE 
ae A 2 UNS a! ald 
[ 
| 
{ 
rding to another anthority (Capt. Sta they), quoted Ly 
Somerville (p. 54), the heights are 19,000 to 29,009 feex 
he north side, and 15,5co on the southers, The difference 
[ the two estima‘es is about the same. The reason of the 
323 
difference is evidently that the south side receives the moisture- 
laden winds from the Indian Ocean. 
Old Forge, Dunmurry JoOsEPH JOHN MurpPHy 
ee Ea) tii ge i 
NOTE ON A POLYDACTYLOUS CAT FROM 
COOKHAM-DEAN 
BY the kindness of Dr. Plumbe, of Maidenhead, I 
have been able to procure one of these cats; and 
from the many curious points he poss: sses, I think a note 
on his peculiarities will interest some of the readers of 
NATURE. 
Readers of Mr. Darwin’s “Origin of Species” are 
familiar enough with the illustration he: gives of corre- 
lation of arrest of development in the deafness of blue- 
eyed cats. Some years ago I showed that our great 
naturalist had fallen into error on this point, and that the . 
correlation is not between the blue eyes and the deafness, 
but between the latter and the sex of the cat. 
I have made a great many inquiries on this point, and 
have completely confirmed my former observation, that 
all perfectly white tom-cats are deaf, and that they have 
blue eyes occasionally, because that item of beauty is 
common among white cats. I have seen many white 
Tabithas with blue eyes, but none of them were deaf. 
My little “Pudge” from Cookham is perfectly deaf, and 
has one blue eye and a yellow one. For the first few 
days after I had him, I thought he could hear a little, but 
am now quite satisfied that his deafness is complete, 
thouzh he is alive to sounds conveyed through solid 
media. A further point of interest is that he is not mute 
as most deafs are, but there is a kittenish shrillness 
in his voice and a loudness in his purring, which are not 
commensurate with his age. I think, therefore, that it is 
posse that early in life he may have heard a little, for I 
now of two instances where perfect mutism accompanied 
the deafness in cats, and I do not know of any contrary 
condition, The cne yellow eye favours my view that 
“ Pudge” may have heard in infancy his mother's voice. 
His sense of touch is extremely acute compared to that of 
another cat I have, but his sight does not seem so sharp 
as that of cats generally is. He has twenty-six digits, 
and these are arranged—seven on each fore limb, and 
six on each hind limb. The supernumerary digits on the 
fore limbs are thumbs, and are placed one on either si je 
of the true pollex, being joined to it, but having no meta- 
carpal bones. In the hind limb the supernumerary digit 
is probably of the same hature, or a supernumerary index, 
being placed on the outer side of the hallux, and attached 
to the tarsus by a completely-developed metatarsal bone. 
Lawson Tair 
eee ee ee ee 
ON ACTION AT A DISTANCE* 
HAVE no new discovery to bring before you this 
evening. I must ask you to go over very old 
ground, and to turn your attention to a question which 
has been raised again and again ever since men began 
to think, 
The question is that of the transmission of force. We 
see that bodies at a distance from each other exert a 
mutual influence on each other’s motion. Does this 
mutual action depend on the existence of some third 
thing, some medium of communication, occupying the 
space between the bodies, or do the bodies act on each 
other immediately without the intervention of anything 
else? 
The mode in which Faraday was accustomed to look 
at phenomena of this kind differs from that adopted by 
many other modern inquirers, and my special aim will 
be to enable you to place yourselves at Faraday's point 
of view, and to point out the scientific value of that con- 
* Lecture delivered at the Royal Tastitution, Feb. 21, 1873, by Prof, 
Clerk Maxwell. 
