u a 



MKTEOROLOOT. 



[BXDEMIO AMD EPIDEMIC DISEASES. 



currying the miasmatic air ; and tlius the baleful in- 

 fluence l largely spread over the adjacent country.* 

 The mouth* of the Mississippi, Amazon, Ganges, etc., 

 afford instances of this kind. 



So far, we hare suggested some of the causes which 

 induce certain endemic and epidemic diseases, that chiefly 

 attack the liver, stomach, \v ; Imt in our own country 

 we hare a constant and fearful source of disease and 

 death, arising from affections of the lungs, including 

 consumption, and complaints of a phthisical character in 

 general. A very considerable proportion of the mortal- 

 ity (about one-sixth) arises from this cause ; and after 

 making due allowance fur unhealthy manufactures, 

 sedentary occupations, &c. , still much is left, as the cause 

 of that elans of disease, to our variable, cold, and damp 

 climate. ' There is, no doubt, much to be said for the pre- 

 valence 1 of phthisis amongst us on the ground of here- 

 ditary tendency; but this frequently disappears in the 

 course of successive descendants ; whilst the mortality, 

 in general, is not lessened, but rather has on annual 

 increase. 



We shall learn much respecting the influence of 'mete- 

 orological conditions on this disease, by comparing the 

 indications afforded by different localities and seasons. 

 In Holland, for example which, of all other European 

 countries, is the most damp ; where a continual exhala- 

 tion of moisture rises from the land, on which an almost 

 constant fog settles at many periods of the year ; a 

 country, in fact, which is nothing better than an 

 immense reclaimed sea-marsh we find that phthisis is 

 alarmingly common. Not only -does a moist climate 

 thus predispose to the disease, but a low elevation is 

 equally as dangerous perhaps on account of want of 

 drainage, and consequent dampness. All these con- 

 ditions meet in Holland, and their results are accordingly 

 fatal to an extraordinary extent. 



But, turning to drier climes, we find the opposite 

 conditions to obtain. In -Northern Russia,- where the 

 range of temperature is excessive, but the air exceedingly 

 dry, consumptive diseases are very rare. Even within 

 the tropics, where the influence of excessive heat induces 

 debility a constant source of the disease yet the dry- 

 ness of the air in some places prevents its occurrence. 

 But we find, that if the inhabitants of those countries, 

 or even the animals common in them, are removed to 

 our climate, the diseases most commonly fatal to both 

 are those of the phthisical type. Elevation above the sea- 

 level, and, consequently, above a stagnant and moist 

 atmosphere, is equally preventive of the disease ; and to 

 patients in the early, or even late stages, the removal to 

 a dry and equable climate is the only chance left for pos- 

 sible restoration to health. 



Having noticed the localities which most favour phthi- 

 BU, we may remark on the influence of the seasons of 

 the year. Winter and spring are generally the most 

 predisposing and fatal ; and in this fact we introduce 

 another element, besides that of moisture namely, 

 the falling temperature of the atmosphere. As autumn 

 approaches, the suspended moisture of the' air, held 

 invisible during the heat of summer, becomes condensed 

 by the loss of caloric which the earth sustains, or rather, 

 perhaps, by the failing supply, owing to the gradually 

 increasing obliquity of the rays of the sun.f The 

 atmosphere then holds the water in the form of minute 

 vesicles, which, as wo have seen, may have gases in 

 solution, and prove a source of irritation to the organs 

 of respiration. The increased sensible moisture rapidly 

 conducts ft way the normal heat of the body ; often 

 checks perspiration ; produces catarrhal affections, or 

 constant irritation of the mucous membrane ; debilitates 

 the system ; and thus gradually induces those conditions in 

 which tuberculous or scrofulous affections are sure to make 

 rapid progress. Sudden changes of temperature, to- 

 gether with the dampness of the air, ensue ; and thus the 

 disease, already planted, is fostered and matured. 

 Possibly, as we have already hinted, the prevalence of 

 free ozone, with a northerly or easterly wind, also accele- 

 rate* the irritation of the bronchial tubes.]: The effect* 

 Set (, p. 11M. l SM ant,, f. 1191. Sec anlt, p. 1187. 



of the advancing winter season are similarly developed, 

 and constantly-recurring atmospheric changes prevail, 

 until the cold winds of early spring complete the work 

 of destruction. Such is an outline of the various causes 

 which produce and accelerate a disease that carries off 

 about one person in every five or six of our population ; 

 and of which, perhaps, scarcely a household in our hind 

 has not had painful experience. 



Our remarks have hitherto been directed to general cli- 

 matic causes, as inducive of phthisical complaints ; and 

 we can here only mention, that impure air, formed in close 

 apartments, factories, workshops, &c. , especially amongst 

 millinery and such trades, is another and fatal cause, for 

 reasons similar to those already assigned. The organs of 

 respiration are kept, under such circumstances, for hours 

 breathing air of a high temperature, and loaded with 

 moisture, and various impurities. The individual, on 

 passing into the open air, instantly encounters a lower 

 temperature, varying with the changes of the season, \o. ; 

 and, gradually, this chain of influences acts precisely in 

 the manner already described, and similar dangerous and 

 fatal results follow. 



Our space, and the limits of our subject, forbid us dis- 

 cussing the effects of climate in producing diseases of a 

 scrofulous character, which are nearly allied to, if not 

 identical with those we have been mentioning. Such 

 are often the direct consequences of exposure to cold, 

 moisture, &c. : and, in every case, a predisposition to 

 those affections is almost certain to become developed in 

 climates of a moist and variable nature ; hence their pre- 

 valence in this country. 



Having glanced at those diseases of the organs of 

 respiration and digestion which result from climatic in- 

 fluences, we may, lastly, make a few observations on 

 some of the most fatal of all endemics or epidemics 

 namely, fevers of the typhoid class. It is familiarly 

 known of these, that they are most common in places 

 where impure air and want of cleanliness are found ; 

 poverty, filth, intemperance, and vice, being their hot- 

 beds. Yet climate has a most marked influence on these 

 diseases, both with regard to the countries and seasons 

 of their appearance. Typhus is completely unknown in 

 the tropical regions, where a profuse and continued 

 perspiration quickly carries off the effete matters of the 

 body ; and it is invariably prevalent in countries which 

 have a cold and moist climate becoming, in fact, an 

 endemic in them: This may arise in a twofold manner ; 

 namely, in part, from the nature of the climate, by its 

 sudden changes checking the perspiration, and inducing 

 internal inflammatory symptoms, with deterioration of 

 the blood ; and also because the moisture of the atmo- 

 sphere always assists in the spread of a disease, for 

 reasons already given. But another and universal 

 cause is found in the depressing influences on the ani- 

 mal system that such climates exercise ; and typhus, 

 of all others, is that which is most attendant on a 

 debilitated state of the functions. Again, in moist 

 weather, the skin often has a greater absorbing power ; 

 and hence a re-entry of excreted humours' into the 

 blood, or of infective and contagious matter, is more 

 likely to take place. It is also noticed, that diseases of 

 the typhoid class are always more prevalent during cold 

 and rainy weather; than in that of a dry and bracing 

 nature, in any locality, whether it be endemically or 

 epidemically affected. 



The report on the health of the navy, for 1860, 

 contains some valuable statistics, showing the influence 

 which climate has on the outbreak and prevalence of 

 disease : and the following summary of the accounts 

 from the East Indian, China, and Australian stations, 

 affords ample verification of the statements wo have ad- 

 vanced in the preceding pages. 



The average ratio of sickness differed very considerably 

 in the different vessels of the squadron : but the variety 

 of employment to which they were subjected, prevents 

 a fair comparison between them. The crews of those 

 vessels most at sea, were much healthier than those 

 employed in the rivers or harbours, or on the coast, for 

 the obvious reason that they were not exposed, in the 



