respiration. The necessity for hydrocarbonaceous food is therefore lessened. Less of the elements of respiration' ought to be taken in the food than would be taken in colder climates. In consequence of the internal increase of temperature, less internal heat is required.

"Exercise increases the heat of the body by increasing the rate of circulation and respiration. In a very hot climate all increase of heat is undesirable. Moreover, the excessive heat renders muscular action impossible, because the circulation is chiefly directed, in consequence of the activity of the skin, to the surface, in order that fluid may be furnished for evaporation, to keep down the heat of the body, to prevent the parching of the surface which otherwise must ensue.

"In consequence of the lessened muscular action, less of the albuminous constituents of the food are required to supply the waste of the muscles.

"Hence, in hot climates, less of both kinds of food should be taken, and nature points this out in the absence of appetite. To force an appetite stimulants are taken, and then the system is overloaded with nourishment. The excessive perspiration requires an excess of liquids; but instead of water alone, sugar and spirit—the elements of respiration—are taken with the water as beer; and the spirit, by its stimulating properties, is doubly injurious.

"The excessive flow of blood to the surface (the consequence of the high temperature), no doubt prevents, for a time, the evils resulting from an excess of the two kinds of food. The chemical changes and evaporation going on in the skin draw the circulation to the surface of the body, just as the flame of the lamp draws the oil up the wick. Whilst the high temperature lasts, this increased action of a flow to the surface is kept up. It is probable that the action of the heart is thereby made feeble by the excessive suction of the skin, as we see it frequently is, temporarily, by the perspiration bath. As soon as the temperature falls, the blood ceases to flow in excess through the skin. According to the degree of cold it is

almost driven from the surface. It accumulates within, and congestions and inflammations are produced. Free action on the inner surface of the body for a time relieves the congestions, and enables the circulation to proceed."-Martin on The Influence of Tropical Climates.

217

CHAPTER XIII.

DISEASES OF THE RAINY SEASON.

ness.

WITHIN this range we meet with the most unhealthy period of Unhealthithe tropical year, the commencement of the rains and its termination; and sometimes from meteoric causes, during the whole of the rains, fevers of the most severe type are prevalent. The temperature at the commencement of the rains falls a great deal; the occasional showers produce a refreshing and delightful feeling; the atmosphere becomes very moist and warm; vegetable and animal life, which before were in a state of dormant vitality, now put on renewed life and vigour; decomposition of animal and vegetable matter, accelerated by the heat and moisture, is very rapid. The atmosphere is very heavy in the mornings and evenings, and the horizon is covered with fog and haze. When the heat of the sun is felt, it produces a great increase in the perspiration, which through the moist air seems to exude from the various pores of the body by transudation, and not by evaporation. The muscular system becomes very much relaxed, the action of the heart weak; there is a congestive state of the internal organs through the venalised condition of the blood, and its receding from the surface.

When the rains have not been plentiful at the commencement, only coming occasionally, and being succeeded by very hot days, when there has not been much thunder and lightning before and during its commencement, fever of the most relaxing and congestive character, or epidemics of yellow fever,

Circumstan

ces producing unhealthi

ness.

Medico

statistical

report.

are generally the consequence. Dysentery and diarrhoea are also prevalent in places where good water cannot be obtained. In Western Africa the commencement of the rains is more unhealthy than their termination, although this period is generally very sickly.

There are many circumstances which combine to render the season unhealthy

1. The occasional occurrence of rain, with the subsequent heat, leads to the formation of stagnant pools, rich in vegetable and animal putrescent matter.

2. The clearing of the fields by farmers in preparation for sowing, deprives the country of the salutary effects of vegetable life, in absorbing the poisons of malarious effluvia emanating from stagnant pools and other sources.

3. The diminished vitality of all the functions of the body; and,

4. The great want of electric agencies in the atmosphere (thunder and lightning), and the consequent diminution of nature's universal disinfectant-ozone.

To prove that the commencement of this season is even more unhealthy to the native population, I shall here quote at length my medico-statistical report of Anamaboe station, from 1st April to 20th May 1861, forwarded to the civil authorities

The numerical relations between sickness and health during the half section of the second quarter of the year, form an interesting data for inquiring into the relative healthiness or unhealthiness of the different sections of the year.

From meteoric circumstances, as well as practical observations, it is now universally acknowledged that the second quarter of the tropical year is the most unhealthy part of the year.

During the first quarter of the year the number of daily patients attending the dispensary to the 31st of March, amounted to 920; whilst during the half section of the second quarter, viz., from 1st April to 20th May (scarcely two months), the number of daily patients was 1114.

The average daily number of patients who attended the dispensary for the first quarter was 12.2, whilst for the sectional part of the second quarter it was 22-2, showing an increase of 10 per cent of daily attendance. From these facts alone it is evident, that at this quarter of the year the station under consideration was far more unhealthy than the preceding. I shall now enter into detail respecting the different diseases treated, and shall follow the division I had formerly adopted, viz. :

I. ZYMOTIC.

II. CONSTITUTIONAL.

III. LOCAL.

IV. VIOLENCE AND ACCIDENTS.

There were no less than 566 cases of zymotic diseases daily treated. The most frequent were-rheumatism, 116; and gonorrhoea, 100. It is remarkable that the number of dysenteric cases was fewer than was expected for the time of the year; this may be accounted for from the fact, that the natives possess potent medicines for it, and, except in extreme cases, they do not apply to the dispensary; so also with fever.

There were 83 cases of constitutional diseases; and 386 of local diseases, of which ulcers (100) were the most frequent; violence and accidents numbered 79 cases.

I shall now conclude by stating, seriatim, the number of daily cases treated in the dispensary, as well as those daily treated in the houses of Poll Tax patients.

I. ZYмOTIC.-Ophthalmia, 60; diarrhoea, 12; dysenteria, chronica and acuta, 30; febris intermittens, 22; hemicrania, 6; rheumatisma, 116; gonorrhoea, 100; strictura urethræ, 40; scabies, 42; dysmenorrhagia, 60; porrigo, 18; orcheitis, 60. II. CONSTITUTIONAL.-Debility, 45; phthisis pulmonalis, 10 ; scrofula, 28.

III. LOCAL.-Hemiplegia, with spasmodic contraction, 60; otitis, 26; bronchitis, 54; pneumonia, 18; dyspepsia, 6; constipatio, 85; odontalgia, 10; psoriasis, 8; ulcers, 100; pediculæ, 8; hydrocele, 9.