SYNOPSIS AND TABLE OF CONTENTS. 
Page. 
Introduction 7 
Value of thyroid as a drug. Importance of a knowledge of the relation 
between the physiological activity and the iodine content. Older 
views on the relation of iodine to the thryoid. Baumann’s discovery 
of iodine in the thyroid. Conflicting views as to the significance of the 
iodine. 
Part I. The parallelism between the physiological activity and the 
IODINE CONTENT OF THYROID. 
A. Historical 11 
Review and discussion of the principal views on this subject. The 
chief objections which have been made to Baumann’s view that 
iodine is an important, not an accidental, constituent of the thyroid. 
The experimental work bearing directly upon the problem. Lack 
of satisfactory methods. 
B. Experimental 19 
Methods, effect of feeding thyroid upon the susceptibility of animals 
to various poisons. Advantages of the method. 
1. Experiments with acetonitrile 21 
Theory of the physiological action of acetonitrile. Effect 
of acetonitrile upon sulphur metabolism, 
a. Experiments on mice 22 
Preliminary experiments and theoretical considerations . — 
The feeding of thyroid increases the resistance of 
mice to acetonitrile. Experiments showing what 
large amounts of the poison may be neutralized by 
very small amounts of thyroid. Delicacy of the 
method for detecting minute amounts of thyroid 
mixed with other substances. 
Conditions influencing the resistance of mice to acetoni- 
trile . — Variations in the resistance of different groups 
of mice to the poison. Influence of season, diet, etc. 
On the manner in which thyroid influences the resistance 
of mice to acetonitrile . — Not a simple chemical inter- 
action between the thyroid and the poison. Bear- 
ing of these experiments upon the theory of the 
detoxicatory function of the thyroid. 
i. Experiments with “iodine free” thyroid 32 
Conception of “iodine free” thyroid. Conflicting 
views as to the activity of such thyroid. Experi- 
mental. Differences in activity between dif- 
ferent preparations of “iodine free” thyroids. 
General conclusions. 
ii. Experiments with commercial sheep thyroids 50 
Relation of dose to physiological effect. 
Outline of methods. Experimental. Paral- 
lelism between iodine content and physiolo- 
gical activity. 
Hi. Experiments with thyroids from various animals. . . 71 
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