PRESERVATION OF HEALTH. 



A HUMAN being, supposing him to be soundly 

 constituted at first, will continue in health 

 till he reaches old age, provided that certain con- 

 ditions are observed, and no injurious accident 

 shall befall. This is a proposition so well sup- 

 ported by extensive observation of facts, that it 

 may be regarded as an established maxim. It 

 becomes, therefore, important to ascertain what 

 are the conditions essential to health, that, by 

 their observance, we may preserve for ourselves 

 what is justly esteemed as the greatest of earthly 

 blessings, and dwell for our naturally appointed 

 time upon the earth. A general acquaintance with 

 these conditions may be easily attained by all, and 

 to render them obedience is much more within 

 the power of individuals than is commonly sup- 

 posed. 



The leading conditions essential to health are 

 I. A constant supply of pure air ; 2. A sufficiency 

 of nourishing food, rightly taken ; 3. Cleanliness ; 

 4. A sufficiency of exercise to the various organs 

 of the system ; 5. A proper temperature ; 6. A 

 sufficiency of cheerful and innocent enjoyments ; 

 and, 7. Exemption from harassing cares. These 

 conditions we shall now treat in succession, taking 

 as our guides the most recent and eminent of phys- 

 iological authorities. 



AIR. 



The common air is a fluid composed mainly of 

 two gases, in certain proportions namely, 20 

 parts of oxygen and 80 of nitrogen in 100, with a 

 very minute addition of carbonic acid gas. (See 

 CHEMISTRY.) Such is air in its pure and normal 

 state, and such is the state in which we require 

 it for respiration. When it is loaded with any 

 admixture of a different kind, or its natural pro- 

 portions are in anyway deranged, it cannot be 

 breathed without producing injurious results. We 

 also require what is apt to appear a large quantity 

 of this element of healthy existence. The lungs 

 of a healthy full-grown man will inhale the bulk 

 of twenty cubic inches at every inspiration, and 

 he will use no less than fifty-seven hogsheads in 

 twenty-four hours. And not only is this large 

 quantity necessary, but the air that surrounds us 

 must be in free circulation, in order that what we 

 expire may be speedily carried away, and allowed 

 to commingle with the atmosphere, which is sub- 

 ject to never-ceasing causes tending to its restora- 

 tion and renewal. 



Now, there are various circumstances which 

 tend to surround us at times with vitiated air, and 

 which must accordingly be guarded against That 

 first calling for attention is the miasma or noxious 

 quality imparted to the atmosphere in certain 

 districts by stagnant water and decaying vegetable 

 matter. It is now generally acknowledged that 

 this noxious quality is, in reality, a subtile poison, 

 which acts on the human system through the 

 medium of the lungs, producing fevers and other 

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epidemics. A noted instance of its thus acting 

 on a great scale is presented in the Campagna di 

 Roma, where a large surface is retained in a 

 marshy state. The exhalations arising from that 

 territory at certain seasons of the year, oblige 

 the inhabitants of the adjacent districts to desert 

 their homes, and escape their pernicious influence. 

 All marshes, and low damp grounds of every kind, 

 produce more or less miasma ; and it is con- 

 sequently dangerous to live upon or near them. 

 Slightly elevated ground, with a free exposure to 

 light and air, should, accordingly, in all cases be 

 chosen for the sites of both single houses and 

 towns. Tanks and collections of water of every 

 kind are dangerous beneath or near a house, 

 because, unless their contents be constantly in a 

 state of change, which is rarely the case, their 

 tendency is to send up exhalations of a noxious 

 kind. Some years ago, Viscount Milton a youth 

 of great promise, and who had recently become a 

 husband and father died of a fever which was 

 traced to the opening of an old reservoir of water 

 underneath the country-house in which he dwelt 

 A similar, but more extensively fatal tragedy took 

 place at a farmhouse in the south of Scotland. 

 Not only did the fanner, his wife, and a female 

 servant sink under a malignant fever, but a son 

 and daughter, and several other servants, narrowly 

 escaped with their lives, and only by removing 

 from the house. It was observed in this case that 

 removal produced instantaneous improvement of 

 health, but a return to the devoted dwelling at 

 once renewed the ailment. On proper investiga- 

 tion, it was found that immediately behind the 

 house was a kind of millpond, into which every 

 kind of refuse was thrown, or allowed to discharge 

 itself; and that this collection of putrid matter 

 had not been once cleared out for a long series 

 of years, no one dreaming of any harm from it 

 The momentous consequences from a cause so 

 trifling, and the consideration that they might 

 have been warded off by only a little knowledge 

 of natural causes, furnish melancholy matter for 

 reflection. Many analogous cases, which might 

 be referred to, demonstrate that we are yet but in 

 the infancy of an understanding of the subject of 

 aerial poisons. 



Putrid matter of all kinds is another conspicuous 

 source of noxious effluvia. The filth collected in 

 ill-regulated towns ill-managed drains collec- 

 tions of decaying animal substances placed too 

 near or within private dwellings are notable for 

 their effects in vitiating the atmosphere and 

 generating disease in those exposed to them. 

 In this case also it is a poison, diffused abroad 

 through the air, which acts so injuriously on 

 the human frame. This was probably the main 

 cause of the plagues which devastated Euro- 

 pean cities during the middle ages. In those 

 days there were no adequate provisions for 

 public cleaning, and the consequence was, that 

 masses of filth were suffered to accumulate. The 



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