No. 3. 



Hygienic Influence of Trees. 



93 



wishes for the success of the cause I am en- 

 gaged in ; assure them also, that success is 

 onlhe high road to prosperous completion. 



Towards you and your readers, I remain 

 most respectfully your friend — in the lan- 

 guage of the lamented and honoured Buel — 

 " With affectionate regard," 



Solon Robinson. 



Philadelphia Sept. 20, 1841. 



For the Farmers' Cabinet. 

 Hygienic Influence of Trees. 



Mr. Editor, — It gives me much pleasure 

 to see the interest that has lately been ex- 

 pressed in the Cabinet, by yourself, and your 

 correspondents, on the subject of the cultiva- 

 tion of trees and ornamental planting around 

 dwellings. That this subject is greatly ne- 

 glected by a large portion of our agricultural 

 community, may be seen by the most cursory 

 observation ; and it is deemed, that any ef- 

 fort the periodicals devoted to the advance- 

 ment of the farming interest in this country 

 may make, in order to call the attention of 

 agriculturists to this important subject, will 

 certainly be in harmony with their object, and 

 no doubt prove beneficial. 



I have long held the opinions expressed by 

 your correspondent, " P." in the August num- 

 ber of the Cabinet, under the caption of 

 "Ornamental Planting;" and since he has 

 so truly expressed the beauty, neatness, and 

 comfortable appearance, which is added to a 

 dwelling by the exercise of a cultivated taste 

 in the arrangement of the trees, vines, and 

 shrubbery which surround it, perhaps a few 

 remarks on the utility of such a course would 

 be acceptable to some of your numerous 

 readers. Permit me, therefore, to follow up 

 " P.'s" suggestion, by adding my humble en- 

 deavour to circulate information respecting 

 this important and interesting subject. 



Many of the blessings which Providence 

 has so bountifully bestowed upon us, contri- 

 bute not only to our pleasure and gratification 

 — not only to beautify and ornament the great 

 temple of nature, but are, added to this, of 

 striking and indispensable importance in the 

 economy and operation of its laws. And 

 among this number we may class trees, al- 

 though I am aware that the opinion is enter- 

 tained in many parts of our country, that 

 trees and vines, planted immediately around 

 dwellings, render them unhealthy. That 

 this is not the case, may be clearly seen by 

 examining for a moment the functions per- 

 formed by them. 



In the first place, they purify the atmo- 

 sphere. 



On the vital importance of atmospheric air, 

 it would be foreign here to dwell ; but the 

 least reflection will show, that its presence ia 



almost constantly necessary to our existence, 

 from birth to death. There is no external 

 agent of which we can be deprived, the ab- 

 sence of which would be attended with an 

 equal amount of deleterious and fatal conse- 

 quences. We may be deprived of light, 

 heat, food, and sleep, for, comparatively, a 

 long period ; but the absence of air, even for 

 a few minutes, is attended with great distress, 

 and, if continued, death is inevitably produced. 

 But it is of equal importance that this air 

 should be pure. 



Air, as inhaled by the lungs, consists of 

 nitrogen and oxygen in the proportion of four 

 parts of the former, to one of the latter ; but 

 when this air is exhaled, it is found to have 

 undergone a material change; a considera- 

 ble portion of the oxygen having disappear- 

 ed, its place being supplied with an equal 

 amount of carbonic acid gas, formed by the 

 union of the carbon of the blood, with the 

 oxygen of the atmosphere. This gas is ex- 

 ceedingly pernicious to animal existence, de- 

 stroying life even when present in, compara- 

 tively, a very small proportion. 



Atmospheric air contains hi maxima -j-rlloTr 

 carbonic acid gas, and fVtyVyV oxygen. A 

 healthy man is computed to consume in one 

 year, 166,075 cubic feet of oxygen (or 45,000 

 cubic inches in one day,) a thousand million 

 men, which, according to some authors, is the 

 estimated population of this globe, must con- 

 sequently consume 166 billion feet in one 

 year ; this is equal to j^-^ of the quantity 

 which is contained in the air in the form of 

 carbonic acid. The carbonic acid in the at- 

 mosphere, would thus be doubled in 1000 

 years, and man alone would exhaust all the 

 oxygen and convert it into carbonic acid in 

 303 times that period. We hence see, that 

 man, independent of the quantity consumed 

 in the respiration of animals and by the pro- 

 cess of combustion, which of course is far 

 greater, would long since have rendered the 

 air incapable of supporting existence; and 

 thus life, producing the seeds of death, the 

 whole animal kingdom would, ere this, have 

 become its own destroyer. 



This evil is obviated by a wise and beauti- 

 ful provision of nature, appropriating this gas, 

 which is so fatal to animal life, as the food 

 and subsistence of vegetation. 



Liebig, in his recent valuable work, has 

 proved by experiments made with the great- 

 est possible accuracy, that the woody tissue 

 of plants is derived almost exclusively from 

 the atmosphere. According to his estimate, 

 40,000 square feet of land was found to yield 

 2650 lbs. of fir wood, of which, not more than 

 91 lbs. taken in the most favourable light, 

 could have been derived from any other 

 source. 



But plants net only render the air respira- 



