478 SECTIONAL TRANSACTIONS.—H, I. 
Finds :— 
Numerous microliths, mainly acute triangular, also cores, scrapers, flakes, 
knife-blades and limpet scoops. Flint derived from the sea-heach on which 
it has accumulated from boulder clay brought down the Irish Sea. The finds 
from this station may be compared with those from numerous others, especially 
those of Western Europe, e.g. Svaerdborg and Mullerup. It is suggested 
that the microliths are related in type to those usually allowed to be of late 
Tardenoisian age, though in date we cannot decide whether they may not be 
later. Animal remains, which would help in dating, are absent. 
SECTION 1I.—PHYSIOLOGY. 
(For references to the publication elsewhere of communications entered in 
the following list of transactions, see p. 506.) 
Thursday, September 13. 
1. Prof. H. E. Roar.—The Analytical Mechanism of the Cochlea. 
2. Mr. T. C. Anaus.—A Recording Katathermometer. 
This instrument is an adaptation of Prof. Leonard Hill’s well-known kata- 
thermometer by which the ventilation conditions of buildings can he measured. 
The cooling-power of the air, depending on its temperature and movement, 
is found by the rate of cooling of a large bulb thermometer of known thermal 
capacity and dimensions. 
In this instrument the lengths of a succession of cooling periods are recorded 
side by side on a moving paper, and a curve is thus drawn whose height at 
any time gives the cooling power of the air in millicalories per sq. centimetre 
per second. 
3. Presidential Address by Prof. G. H. F. Nurratn, F.R.S., 
on Symbiosis in Animals and Plants. (See p. 197.) 
—— ee 
4, Prof. H. ZwaarpemaKer. — Bio-radioactivity and Humoral 
Environment. 
(1) Normal bio-radioactivity depends on the normal potassium content of 
the cells. (2) An important part of this content is the potassium in the super- 
ficial layers of cells. (8) The ionic balance is itself a condition. A heart 
perfused with Noyons’ glucose solution shows the balance at its lowest level. 
When the balance has been brought to a higher or lower level than the normal, — 
there is, respectively, an increase or decrease of radioactivity. (4) The sensi- 
tivity of the tissues to radioactivity is regulated by the blood hormones, so that 
a normal activity is guaranteed under very different conditions. 
5, Prof. R. Macenus.—Carbon Dioxide and Adrenaline as Regu- 
lating Factors for the Musculature of the Bronchi and 
Pulmonary Vessels. 
Experiments by Lohr and De Lind van Wijngaarden on surviving perfused 
cat’s lungs in the author’s laboratory have showed that the bronchio-spasm 
produced by defibrinated or hirudinised blood, &c., is relaxed by the addition 
of from 1.4 to 30 per cent. of CO, to the air respired. Carbon dioxide in con- 
centrations from 1.4 per cent. upwards causes in most cases constriction of the 
lung vessels, but when adrenaline is present in the blood in amounts over 1 per © 
milliard the effect of CO, is to cause dilatation. Alteration in the concentrations — 
of oxygen and nitrogen in the blood are without influence on the bronchial or — 
vascular tone. 2, 
It is concluded, therefore, that carbon dioxide in physiological concentra- _ 
tions helps to keep the air-way patent, and, in presence of physiological amounts — 
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