214' Doyle' s Hints to the Irish Peasantry^ 



2. Hints addressed to the Small Holders and Peasantry of Ireland, on 

 Road-making, and on Ventilation, &c. &c. Dublin, 1820. 12mo. Is, 

 This is another valuable little work. The article on the importance 

 of pure air ought to be read, and, if possible, understood and acted on, by 

 every master and mistress of a family. Very few indeed, even of those 

 who are classed amongst the respectable part of society, are aware of 

 the injury which the health sustains by breathing in an atmosphere which 

 has been deprived of part of its oxygen, either by our own respiration or 

 that of other persons, or by the burning of candles or lamps. If the 

 middling classes about London understood the subject, would they be con- 

 tent to rent houses with such low ceilings, especially to the bed-rooms, as 

 we see rearing up every where round the metropolis ? Unquestionably 

 not : they would refuse to occupy such houses, and the builders would be 

 obliged to alter their proportions in building them. 



" Since air is passing through our lungs every moment of our existence, 

 it is of immense importance to have it pure. The young and healthy may 

 not quickly perceive the changes or impurities of the atmosphere they 

 breathe ; but the delicate, the sickly, and the aged are powerfully influenced 

 by its qualities. From the interesting and satisfactory experiments which 

 learned men have made, it has been proved that the lungs of a full-grown 

 man contain, on an average, five quarts of air ; he draws in and breathes out 

 a seventh part of this quantity at every breathing. If he draws in and lets 

 out breath twenty times in a minute, a quantity of air which would weigh 

 53 lbs. would pass through his lungs in twenty-four hours. Farther, the 

 atmosphere is composed oi cevtwaJJuids or gases, of which one, caWedo jri/gen, 

 which is indispensable to animal life, forms a fifth part, and the other four 

 parts are more or less pernicious. Again, in the process of passing through 

 the lungs, this oxygen, this pure part, becomes consumed or withdrawn 

 from the atmosphere in a considerable degree, leaving the air more and 

 more free from it at every breathing, until it becomes pernicious in the 

 extreme ; for the change in the quality of the air is more than merely 

 withdrawing the oxygen ; the place of this pure portion is supplied by 

 what is commonly called fixed air, which is fatal to life. Thus does the 

 process of breathing not only take from the atmosphere the portion of it 

 on which life depends, but actually renders it poisonous. To admit fresh 

 air continually is therefore very necessary; and of this, for healthful 

 respiration, a man requires three gallons each minute." (p. 25.) 



In speaking of the state of ventilation in Ii'ish farm-houses and cottages. 

 Ml-. Doyle says.: — "It frequently happens that the family of a small 

 holder or labourer is so poor as to have only the means of building one 

 wretched little bed-room, perhaps 8 or 10 ft. square. In this the father 

 and mother, and half a dozen children, and occasionally a cousin or two, 

 are obliged to lie. Now, there is no matter (not absolutely poisonous) 

 more prejudicial to health than that which arises from the human body; I 

 mean, through the pores of the skin, as well as from the breath; and in this 

 case I am supposing eight or ten persons to pass seven or eight hours in 

 a room barely large enough to hold them when packed closely in bed. 

 Well, the air, on account of the heat which it has acquired in passing 

 through the lungs of this family party, stretched higgledy-piggledy on their 

 straw, becomes lighter than the surrounding air, and rises to the ceiling : 

 no outlet being there for its escape, it remains till it becomes cool, when 

 it will descend. Up goes another and another whifF of heated and rarefied 

 air at every breathing, which in turns fall down again; and in the circuit 

 which it thus takes, the same air passes through the lungs of all the persons 

 in the bed, who take in at each breathing a new portion of impure matter, 

 and loses every time that it is drawn in an additional portion of its life- 

 sustaining principle. If the inside door be open, the quantity of cool air 



