March 16, 1882] 
attributed to heredity.” Now in order to be admis ible, a theor j 
y. 
must harmonise with all the phenomena. It is an admitted 
axiom in science that even one ‘‘ negative” case is all but fatal 
to a theory. Dreams occasionally ‘‘come true,” and persons 
who have been impressed by such coincidences base on them a 
belief in ghosts. But the great majority of dreams do 7o¢ come 
true, and therefore science does not recognise the existence of 
ghosts. Careful investigation may bring out many explanations 
of a few cases of deaf ‘‘ mutes” apparently speaking with the 
accent of their native districts, without attributing the pheno- 
mena to heredity. But if dialectal accent is hereditary, how are 
we to explain the 400 cases cited by Prof. Bell (to name one 
competent observer alone) in which no such accent was observ- 
able ? 
Mr. Axon quotes (apparently with approval) M. Hément’s 
declaration of inability to conceive ‘‘how in losing the use of 
speech, deaf mutes should retain the unconscious memory of 
accent.” I wish to suggest that such phenomena may be due to 
automatic activity of the cerebral tissue. In his la t ‘‘ Causerie,” 
n the Raffel, M. Victor Meunier mentions the case of a young 
man, an inmate of a French asylum, who six years ago became 
deaf with the right ear through the effects of typhoid fever. He 
is occasionally conseious of sounds on the right, or deaf side, of 
which the left ear gives no indication vhatever. He hears entire 
sentences, distinctly articulated, and as these are sometimes of 
an offensive character, they have involved him in many quarrels, 
as he has attributed them to perfectly innocent- persons who 
have chanced to be near his right side at the time. Notwith- 
standing this hallucination, his judgment has remained sound, 
and having discovered that he sometimes hears (with his right 
ear) absent or stopped clocks strike loudly, he has learned to 
disregard any sounds but those which his left ear communicates 
tohim. M. Luys, cf the hospital of La Salpétirére, gives many 
illustrations of such automatic activity. 
Remembering that memory has a physiological basis, and 
believing in the psychical basis of language, I find it far less 
difficult to conceive that after the loss of speech deaf mutes 
should retain the ‘‘unconscious memory” of accent than that 
accent should be hereditary. Indeed the loss of speech might 
even be favourable to such retention ; for the particular cells 
concerned might keep the original impression unimpaired by 
subsequent impressions, to be accurately given forth again when 
the requisite conditions came into operation. 
This does not explain the case of Daniel Fraser, said to have 
been mute from his birth ; but, on the other hand, ‘‘ one swallow 
does not make a summer.” F. J. FARADAY 
Manchester, March 4 
Vignettes from Nature 
WitH all due deference to Dr. Carpenter, for whose supreme 
authority on all matters of biological fact I have, of course, the 
profoundest respect, I must plead that he evidently has not 
looked into my little book, ‘‘ Vigne'tes from Nature,” but has 
taken his statements at second hard from the necessarily con- 
densed account given in Mr. Wallace’s kind review. Had he 
consulted the book itself, he would have found most cf my 
remarks intentionally so guarded as to escape his strictures. 
First, as to the sharks. Dr. Carpenter says, ‘‘ None of these, 
in the judgment of Mr. Grant Allen and Mr, Wallace, surpassed 
the forty-feet sharks of the present time”; and he goes on to 
speak of a Carcharvodon tooth from the Crag, 4 inches long by 3 
broad. Now, in ‘‘ Vignettes,” p. 76, I wrote, ‘‘The teeth of 
what seems to have been the biggest known fish, a prodigious 
shark, are dredged up in the modern ooze of the Pacific. . . 
They have become extinct at a very late date.” I took my facts 
from Dr. Giinther’s ‘‘ Study of Fishes,” p. 321, where we read 
as follows :—‘‘ Carcharodon teeth are of very common occurrence 
in various tertiary strata. . . . Some individuals attained to an 
immense size, as we may judge from teeth found in the Crag, 
which are 4 inches wide at the base, and 5 inches long... . 
The naturalists of the Challenger expedition have made the highly 
interesting discovery that teeth of similar size are of common 
occurrence in the onze of the Pacific, between Polynesia and the 
we:t coast of America, . . . The gigantic species to which these 
teeth belonged must have become extinct within a comparatively 
recent period.” In short, the very shark which Dr, Carpenter 
claims as tertiary, I had previously claimed as also nearly 
modern. 
Dr. Carpenter further says, ‘‘Is it clear that Z7zdacna is the 
largest known Mollusk? I should have thought it exceeded by 
NATURE 
459 
the gigan‘ic Ammonitide, &c.’’ But if he will turn to ‘ Vignettes,” 
p- 75, be will see that I wrote, ‘‘ No fossil diva/ve molluscs to 
my knowledge are as big as . . . tridacna.” The word 1 have 
italicised makes all the difference. On p. 77 Dr. Carpenter will - 
see that allusion is made to the big Cephalopods, though perhaps 
none of these were very much larger than the largest modern 
gigantic squids, 
As to the other points, they are really matters of language, and 
T wll not take up your space by answering them in detail. When- 
I spoke of ‘our whales,” { certainly did not mean to exclude 
extinct whales :; I merely meant to contrast them with the great 
secondary Saurians. Nor did I say that horses, elephants, &c., 
had been steadily increasing in «ize from ‘‘the earliest epoch of 
their appearance to the present day”; I said, ‘‘to the recent 
pericd,” which is quite another thing. As 1 was writing for 
popular readers, not for biological critics like Dr, Carpenter, I 
felt bound to use the vagne but comprehensible language of 
ordinary life ; and so I described the mammoth as **recent,”” 
quite justifiably, I think, for my existing purpose. No technical 
words were used in the volume, and it was impossible always to 
find popular ones quite free from objection. But if Dr. Carpenter 
will kindly read the short ckapter in question, I venture to think 
he will be willing to withdraw his present strictures. The object 
was merely to combat the vulgar notion that all the animals of 
all geclogical ages were prsitively gigantic; and in doing so, 
almost every animal mentioned by Dr. Carpenter was expressly 
adduced as an example. 
In answer to #1, I should like to add that I used the word 
“aecidental” in a strictly Pickwickian sense. 
Grant ALLEN 
Miss Cobbe and Vivisection 
WILL you allow me as one not only ardently interested in the 
pursuit of vivisection as a means of extending our knowledge, 
but also asa sincere hater of unnecessary cruelty to animals, to 
state the following facts which I know to be true :— 
Some little time ago Miss Frances Power Cobbe, who has so 
identified herself with the cause of anti-vivisection, called on a 
distinguished man of science to endeavour, by persuasive speech 
and z2vd-voce argument, to gain him over to her cause. ‘Three 
points were observable in Miss Cobbe’s outward presentment, 
viz. : she had an ostrich feather in her bonnet ; a bird of paradise 
in, on, or near her muff; and she carried an ivory-handled 
umbrella ; consequently the distinguished man of science replied 
as follows :— 
‘* Madam, charity tegins at home; when you have given up 
wearing ostrich feathers, which are plucked from the diving bird, 
causing the most exquisite pain, and birds of paradise, which, in 
order to enhance their beauty and lustre, are sk7zned alive ; when 
you have abjured the use of 7vory, because you know that the 
tusks are cut out of the dying elepbant’s jaw, then, and then 
only, come and uphraid me with the cruelty of my operations. 
The difference between us is, Madam, that 7 inflict pain in the 
pursuit of knowledge, and for the ultimate benefit of my fellow- 
creatures ; you cause cruelty to be inflicted merely for your 
personal adornment... ” H. H. JOHNSTON 
Zoological Gardens, Tue day 
The Electrical Resistance of Carbon under Pressure 
From the abstract of the proceedings of the Physical Society, 
given in NaTurn, vol. xxv. p. 426, I learn that Prof. <S. 
Thompson has been making some experiments which tend to 
show that the observed diminution of the resistance of carbon 
urder pressure in such instruments as the carbon relay, rheostat, 
and microphone-transmitter is really due to the contact between 
the electrodes and the carbon. No doubt the greater portion of 
the observed diminution of resistance is due to this cause, and I 
have already pointed out in my paper on ‘the Influence of 
Stress and Strain on the Action of Physical Forces,” Part ii., 
Electrical Conductivity, an abstract of which (NATURE, vol. xxv. 
p- 401) was read before the Royal Society on January 26, that 
the effect of a given amount of longitudinal traction or compres- 
sion per unit area onthe electrical resistance of some carbon rods 
was not greater than is the case with the metals tin ard lead, for 
whereas a stress of 1 gramme per sq. cm. produced a variation of 
conductiyity of from 7684 X Ic-12 to 11420 10-12 per unit in the 
case of five carbon rods, the corresponding numbers were, with 
tin and lead, 10540 10-12 and 17310 X 1c-12 respectively. » The 
‘carbon rods were of the sort ued for the purposes of electric 
~ 
