321 
1916-17.] Observations on the Blood in Gas Poisoning. 
gas attack, in his dugout; and, on a second occasion, August 3, 1916, 
while trying to extricate an officer from his dugout after the explosion of 
a shell. On the latter occasion he was rendered unconscious. His case is 
complicated by neurasthenia following shell shock. He suffers from 
persistent pains in the head and dyspepsia, with frequent vomiting. His 
blood shows: — polymorphs 36'2 per cent., lymphocytes 55’4 per cent. The 
number of leucocytes per cubic millimetre on the last examination was 
17,000. An analysis of the cases as arranged in the above groups is given 
in Table V. 
Table V. — Analysis of Cases in regard to Relation between Percentage 
of Lymphocytosis and Severity of Symptoms. 
Group I. Lymphocyte percentage less than 40 per cent. 
1. Slight cases. (Total eight.) -Nos. 5, 7, 10, 11, 19, 20, 22, 23. 
2. Cases originally moderately severe. (Total seven.) Nos. 16, 24, 29, 36, 38, 40, 50. 
3. Old cases occurring many years ago, and associated at the time witli severe symptoms. 
(Total two.) Nos. 42, 43. 
4. Case insufficiently recorded to determine classification. (Total one.) No. 18. 
Group II. Lymphocyte percentage of 40 per cent, or over. 
1. Slight cases. (Total four.) 14, 31, 44, with slight respiratory symptoms ; 35, with 
no symptoms. 
2. Intermediate cases. (Total three.) 1, 21, with gastric symptoms ; 28, with respiratory 
symptoms. 
3. Severe cases. (Total twenty-four.) 
(a) Symptoms respiratory. (Eighteen cases.) 2, 8, 9, 12, 25*, 26, 27*, 30, 33, 
*34, 37, 39, 41, 45, 46, 47, 48, 49*. 
( b ) Symptoms gastric. (Four cases.) 13, 15*, 25*, 49*. 
(c) Nervous symptoms. (Eleven cases.) 
i. Neurasthenia, Nos. 15*, 27*. 
ii. Headache, Nos. 15*, 26*, 32. 
iii. Tremor, Nos. 3 f, 4, 6 f. 
iv. Insomnia, Nos. 46*, 47*, 48*, 49*. 
4. Case insufficiently recorded to determine classification. (Total one.) No. 19. 
The cases marked with an asterisk appear in the list in more than one place, as several 
prominent symptoms were present. The two cases marked with a dagger are of interest 
because, in addition to the other symptoms, they exhibit a long-continued conjunctivitis 
which has persisted for months after the tissue cells originally injured must have been 
replaced by new ones. 
The type of leucocyte which is increased is the small lymphocyte with 
relatively large, deeply staining nucleus, and comparatively little proto- 
plasm. In a few cases, e.g. 49, there was a fair sprinkling of larger 
lymphocytes, with a broader rim of protoplasm and larger nucleus. No 
other type of blood cell appeared to be influenced in any constant fashion. 
The last point which arises is the question of the cause of the blood 
change. A relative or absolute lymphocytosis is met with as an accom- 
paniment of a large number of pathological conditions. Of the diseases 
VOL. xxxvii. 21 
