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ANALYSIS OF TABLES 1, 2, 3, AND 4.

Comparison of percentages of frequency of occurrence of superiority of temperature of a side and of

equality of temperature of the two sides.

(F) Cases where the higher of the two temperatures compared is not below 35.5° C.

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Left side Right side Equality

(G) Cases where the higher of the two temperatures compared is not above 34:55° C. 105 26.9231

60 25.0000

45
23:0769

105
165
423077

120
50.0000

150 76.9231

270 120 30.7692

60 25.0000

0

75

23:3334 60.0000 16.6666

Total......390

Total..

240

Total......195

Total......450

No satisfactory conclusions can be drawn from the above analysis. In two of the tables (Tables 1 and 4) the percentage for superiority of the left side diminishes at the lower temperature, while in the other two tables it increases at this temperature. In Table 1 the percentage for superiority of the right side is greater at the higher temperature, while in the other three tables it is greater at the lower temperature. In one case (Table 1) equality of temperature shows an increase at the lower temperature; but in Tables 2 and 4 the percentage of this condition is diminished, and in Table 3 no case of equality is found at the lower temperature.

Summing up the results of all our analyses, it would seem that the degree of absolute temperature has no definite influence on the frequency of occurrence of superiority of temperature on either side of the head, and but a limited influence, at best, on equality of temperature of the two sides; at every absolute level each of the three conditions may be found with varying frequency at different times.

It would, seem, therefore, that the rises and falls of absolute temperature, by which the balance of superiority of temperature is shifted from one side to the other, or by which equality of temperature of the two sides is brought about, follow, in a great measure, no definite law, but are governed by agencies which are liable to constant variation. The two sides are not, then, like two furnaces which have unequal limits of range, but in which the production of heat is carefully controlled so as to cause simultaneously in both regular increases or diminutions of energy, one surpassing or falling below the other only at certain fixed points, and then simply because the thermal limit of one has been reached; but they rather resemble two furnaces of equal range, but the fires of which are, to a certain extent, managed independently of each other and with a variable degree of regularity, the relative powers of the two being thus uncertain, and either one likely at any moment to surpass the other.

There is one other point to be noticed in conclusion, namely, the comparative degree of difference of temperature between the two sides of the head at different absolute levels. Looking back to the analysis of absolute temperatures on page 26, we see that, with one exception, the average degree of difference of temperature between the two sides is greater at the temperatures below 35° C. The single exception is in Table 4, where the average difference of temperature in the cases in favour of the right side is slightly less at the lower temperature. As the absolute level rises, therefore, the average difference between the two sides would seem to diminish ; but a glance at the tables will show many exceptions to this rule, the irregular and unequal rises and falls of the temperatures of the two parts bringing about as great differences even near the extreme limit as those shown at the lower levels.

The causes of these irregularities are undoubtedly many and complicated, some existing in the brain and some in the tissues external to the latter. The writer has elsewhere dealt to a certain extent with some of these causes, and it suffices to say now that their existence and unmanageable nature must throw grave doubts on the reliability of conclusions drawn from examinations of the temperature of the head in disease, unless much greater latitude be given to normal variations of temperature, both absolute and relative, than has generally been accorded by those who have given special attention to this subject.

PRINTED BY J. E. ADLARD, BARTHOLOMEW CLOSE.

ON THE EFFECT OF

VOLUNTARY MUSCULAR CONTRACTIONS

ON THE

TEMPERATURE OF THE HEAD.

BY

J. S. LOMBARD, M.D.,

YORMERLY ASSISTANT PROFESSOR OF PHYSIOLOGY IN HARVARD UNIVERSITY,

ASSISTED BY

FREDERIC H. HAYNES, M.D.,
PHYSICIAN TO THE WARNEFORD HOSPITAL, LEAMINGTON,

LONDON:
H. K. LEWIS, 136, GOWER STREET.

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