The need of ventilation.

  • Watson, Charles.
Date:
[1867?]
Catalogue details

Licence: Public Domain Mark

Credit: The need of ventilation. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    THE NEED OF VENTILATION. “ God has decreed that a certain proportion of oxygen shall suffice for the aeration of only “ a fixed and determinate quantity of venous blood. If we adapt our circumstances to “this laic, we reap our reward in comfort and health. Whereas if we transgress it, and “ persevere in breathing an atmosphere containing less than the requisite quantity of oxygen « and more than the usual quantity of carbonic acid, we have no more right to expect to “enjoy health, energy, and activity of mind and body, than to expect afire to burn with- “out air, or a fish to live out of xcater.” “ Before entering the Lungs, the atmospheric air consists of 21 parts of oxygen and 79 “ parts of nitrogen, with a very small trace of carbonic acid. When it is expelled, how- “ ever, it is found to be greatly altered. The bulk of the air expired continues to be nearly “ equal to that inspired, but, on analyzing its composition, we find that rather more than “8 out of the 21 parts, or nearly two-fifths of the oxygen have disappeared; and their “place has been supplied by unequal volume of carbonic acid. The nitrogen is the only “constituent which remains almost unaltered. Along with this expired air, a large quan- “Uty of watery vapour and some animal matter are also thrown out.” “ The only kind of air, then, which is calculatedto sustain animal life in permanent health “ and vigour, is that containing the precise ingredients in the precise proportions ascertained “to exist in the atmosphere. If the relative quantity of any ingredient be increased or ‘t diminished, the proper constitution of the blood will be immediately changed, and the “ general health endangered.” “ Animal heat is really the produce of a physiological combustion, and bears a direct “relation to the intensity with which the carbon and oxygen are brought in combination.” “ Typhus and putrid fevers, consumption, scrofula, delicate health, head-aches, and “cutaneous, bilious, and nervous attacks are caused by inspiring vitiated air. About one- “fourth of the annual deaths of Great Britain are caused by consumption, and nothing “ so soon diseases the lungs as vitiated air.” “ Keeping in mind that every pair of lungs consumes on an average about 2 J hogsheads, “ or 1000 pints of air per hour, in the oxygenation of rather more than 1 hogshead, or 426 “pints of blood, and also the numerous other sources of impurity of air, such as fires, lights, and the cutaneous and pulmonary exhalations, there can be no difficulty in under- “ standing how indispensable a regular supply of pure air must be to the health and comfort “of every one who remains even for an hour within the four icalls of a room.” “ In the deplorable examples of the miseries caused by ignorance of the simplest laws “ of the animal economy, the effects arising from the absence of a due proportion of oxygen “ in the air inhaled, are portrayed in appalling colours. But those which are produced by “breathing an atmosphere vitiated to a much smaller extent, although not so strikingly “ obvious, are by no means less real.” Extracts from Dr. Combe's “Principles of Physiology.” VENTILATION is not Draughts! What is it? It t« a fact that should never be lost sight of in connection with Ventilation, viz.:— That strong draughts or currents of air are not necessarily ventilation; these do as much or more injury to persons and animals than the bad air does. There may be strong draughts in or through a room, and yet the room not be ventilated—some persons corn- planing of the draughts, and others of want of ventilation. The great problem inventila- txon ^at required solving was, a thorough exchange of bad air for good air, in any quantity, in any latitude, and at all seasons, without dangerous and perceptible draughts, “n2/ nundirr of persons and animals, atnd for all kinds of buildings and ships. This problem Mr. Watson has practically solved. A