350 SECTIONAL TRANSACTIONS.—I. 
Methods employed to estimate the relative importance of the part played by the 
induced leucocytosis in the production of artificial acquired immunity : (1) general ; 
(2) special methods. 
Description of the effects of induced leucocytosis on sundry cases of various 
infections. 
Account of the immunity effects produced by specific antigens alone compared 
with effects produced by leucocytosis alone. 
Account of the immunity effects produced by both in combination. 
Some of the more interesting experiments described in greater detail. Deductions 
drawn : (1) with a fair degree of conviction ; and (2) tentatively, from the experiments 
made up to date. 
Outline of continuation of investigations. 
8. Dr. B. A. McSwinry.—The Tonus and Contractile Mechanisms of the 
Stomach. 
The functional activity of the stomach depends on two properties of the smooth 
muscle: (1) ‘Tonus,’ or postural activity ; and (2) movement, or the contractile 
mechanism. These properties have been demonstrated by the action of drugs and the 
stimulation of the nerves. 
The action of a stimulating drug on the isolated strips of the stomach wall has been 
shown by Brown and McSwiney. The results demonstrate that in the region of the 
fundus the ‘ tonus’ mechanism is well developed ; a drug such as pilocarpine brings 
about a permanent shortening of the muscles fibres. In the pyloric region, however, 
‘tonus ’ changes are difficult to elicit, the base-line which indicates the length of the 
muscle fibres maintaining a constant level. 
The contractile mechanism is developed to the greatest extent in the pyloric region, 
augmentation of movement being most pronounced on addition of the drug; in the 
upper regions the rhythmic contractions of the cardia and fundus are normally weak 
and irregular and may be diminished by pilocarpine. In the intermediate regions 
contractions and tonus changes are both well marked. 
Stimulation of the peripheral end of the vagus nerve gives further evidence as to 
separation of these functions. McCrea, McSwiney, and Stopford have shown that the 
effect of the stimulus depends on the condition of the peripheral mechanism. In 
the active stomach, which is maintaining an entogastric pressure, stimulation of the 
nerve results in a fall of pressure; movements, if present, cease, and relaxation 
occurs. Augmented contractions ensue later, if contractions were absent before the 
stimulus: initial movements now occur. In the inactive organ, which does not 
maintain an entogastric pressure, there occurs a rise of pressure, and movements, if 
present, are augmented and sometimes accelerated. 
Recently McCrea and McSwiney have separated the pyloric region from the 
remainder of the stomach, leaving its nerve supply intact. The pyloric region on 
stimulation shows well-marked contractions, with absence of relaxation or postural 
adaptation. The tonus changes, namely relaxation, are limited to the upper regions 
of the stomach. 
9. Mrs. Poytiis Kerriper.—Nature and Use of Glass Electrodes. 
AFTERNOON. 
10. Lecture by Mr. J. E. Barnarp, F.R.S., on The Microscopic 
Observation of Small Bodies. 
Monday, August 31. 
Mornine. 
11. Presidential Address by Prof. A. V. Hitt, F.R.S., on The 
Physiological Basis of Athletic Records. (See page 156.) 
12. Dr. J. M. Dunoan Scorr.—Action of Strychnine on Bulbar Vasomotor 
Reflexes. 
Doses of 0.05 mgm. of strychnine nitrate applied to the depressor point cause the 
depressor reflexes from the vagus and somatio nerves to disappear. Whether a vagal 
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