970 
numerals were fully developed in India not 
much more than two centuries before this 
time. We are thus brought very close to the 
time of the origin of the powerful symbols 
which we use for computation. Further, the 
passage is of interest because it explicitly 
mentions the Babylonian contributions to as- 
tronomy and we must conclude that if the 
writer at that early date had known of any 
connection between the Babylonian number 
system and the Hindu he would have men- 
tioned it. The passage in question is pre- 
sented by M. F. Nau in some notes on 
Syrian astronomy. M. Nau quotes from the 
writings of one Severus Sebokt, bishop of the 
monastery at Quennesra, on the Euphrates, 
near Diarbekr. This Sebokt was famous in a 
literary way and made his monastery a center 
of Greek learning. He himself was originally 
from Nisibin towards India, and it is not be- 
yond the bounds of probability that there he 
came into contact with the learning of the 
Hindus. 
Sebokt claimed for the Syrians the inven- 
tion of astronomy. He stated that the Greeks 
went to school to the Chaldeans of Babylonia 
and these, he adds, are Syrians. This state- 
ment of Sebokt’s is supported by the most 
recent investigations in the history of the 
development of science. An interesting article 
on this subject was published by F. Cumont, 
entitled “Babylon und die griechische As- 
tronomie.”* Sebokt concludes that science is 
not the peculiar property of the Greeks, but 
rather open to all men. 
The subsequent passage contains the refer- 
ence to the numerals and I translate from the 
French translation given by M. Nau: 
I omit now to speak of the science of the 
Hindus, who are not Syrians, of their subtle dis- 
coveries in this science of astronomy—( discoveries) 
which are more ingenious than those of the Greeks 
and even of the Babylonians—and of the easy 
method of their calculations and of their computa- 
* Journal asiatique, Vol. 16 (10th series), 1910, 
pp. 225-227. 
° Neue Jahrbiicher f. das klass. Altertum, Gesch. 
und deutsche Literatur und f. Pddagogik, 1911, 
Vol. 27-28, pp. 1-10. 
SCIENCE 
[N.S. Vou. XXXV. No. 912 
tion which surpasses words. I mean that made 
with nine symbols. If those who believe that they 
have arrived at the limits of science because they 
speak Greek had known these things, they might 
perhaps have been persuaded, even though a little 
late, that there are others who know something, 
not only the Greeks, but even people of a different 
language. 
Louts ©. Karpryski 
UNIVERSITY OF MICHIGAN 
SPECIAL ARTICLES 
THE SOURCE OF THE CURRENT OF INJURY 
WHEN we connect calomel electrodes filled 
with KCl solutions of the same concentration 
with the uninjured skin and an injured spot 
of an apple, respectively, we notice a potential 
difference from between 40 to 100 millivolts, 
the injured spot of the apple being negative 
to the uninjured spot. We have made experi- 
ments which indicate that the so-called current 
of injury is due to a difference of potential 
which exists on the inside of the skin of the 
apple probably at the limit between the skin 
and an adjacent layer of cells, the latter 
being negative to the former. The proof for 
this statement is found in the following facts. 
1. When we form a cell of the type 
n/10 KCl | Apple | x/10 KCl 
uninjured injured 
side side 
the E.M.F. remains the same no matter how 
deep a hole we make into the apple. As soon, 
however, as the n/10 KCl approaches the 
inner surface of the apple the E.M.F. sud- 
denly becomes smaller and finally disappears. 
This is not due to an injury of the skin 
itself, since a change in the concentration on 
the outer surface of the skin still gives the 
same change in E.M.F. as in an intact apple. 
The disappearance of the “ current of injury ” 
when the salt solution reaches the inner sur- 
face of the membrane of the apple is there- 
fore due to the disarrangement or destruction 
of a specific layer on the inside of the surface 
film of the apple. 
2. By pressing the surface of an apple with 
a finger we can destroy the adjacent layer on 
the inside of the skin without injuring the 
