THE INJURY CURRENT OF NERVE 
285 
(In all the succeeding statements of the potential differences, point (1), point (2), etc., means a 
point on the longitudinal surface distant 1 centimetre, 2 centimetres, etc., from the upper cross section). 
(a) The resistance of piece of 5 centimetres was 14,800 ohms, or 2,960 per centimetre. 
The potential differences between points on the longitudinal surface and the upper cross 
section were — 
Point (1) + '000264 Daniell 
,, (2) + -000264 
„ (3) + -000132 
„ (4) 4- -000132 
Other cross section ,, (5)* + o 
The differences were therefore normal in direction, but small. 
(b) The nerve now (ten minutes after its removal) was placed in tap water, 
and left in this for twenty minutes. Upon removal it was dried in filter paper. 
It was now slightly rigid, and measured 5 centimetres. Its resistance was 20,200 ohms, 
or 4,040 ohms per centimetre. 
Point (1) + 
„ (*) + 
„ (3) + 
» (4) + 
Other cross section „ (5)* 4- 
(c) The nerve was now replaced in tap water, and left for a further twenty minutes in this. The 
results of this, as of similar successive repetitions of the same manoeuvre, are given in the 
following table : — 
(d), (e), ( f), (g), (/;), (/) in the table, represent repetitions of the same manoeuvre, and the subse- 
quent observations made. 
After this,'_that is to say, four hours after the death of the dog, the nerve was placed in tap water, 
and examined after being in it twenty-four hours ; the nerve was still tense, rigid, and swollen, and 
provided a demarcation current in the normal direction, as in the table line (j). 
A similar observation was made the next day (k), the nerve having been now forty-eight hours in 
tap water — it was still rigid. 
The Intact Nerve of the Other Side of the Same Animal 
The left sciatic nerve was excised immediately after the first examination of the degenerated nerve was 
completed, and whilst the degenerated nerve lay in its first bath of tap water. This nerve was examined 
and then treated exactly in the same manner as the degenerated nerve was treated, the observations upon 
this nerve alternating with those upon the other, and so also the immersions in tap water. The main 
facts of this examination are given on following page. 
•002772 volt potential differences to upper cross section. 
■003960 „ „ „ 
•007128 „ ,, 
•OO8712 „ „ „ 
•000132 ,, ,, ,, 
Points marked thus * are in each case the second cross section 
