These figures, undoubtedly, seem large, 

 but if I should say that 200 colonies of bees 

 require as much air as their owner, you 

 would not be surprised, but think the esti- 

 mate quite small. Now, Gen. Morin. of 

 Paris, (see Smithsonian Reports,) has fur- 

 nished us the best of proof, (experimental, 

 not theoretical), that in close apartments, 

 in order to keep the atmosphere around 

 him sufficiently pure, man requires over 

 2,100 cubic feet of air per hour, a result sub- 

 scribed to by the best authorities in Europe. 

 This is largely in excess of the amount 

 required by 200 colonies of bees, supposing 

 each to consume l}i lbs. of honey per 

 month. 



But where did the bees in close confine- 

 ment get their supply of air ? There is no 

 proof given that the receptacles were air- 

 tight. Adair's test only proves that the 

 outlet was immeasureably smaller than the 

 inlet; and it is not claimed that Prof. 

 Cook's hive had no crevices through which 

 a limited supply of air might not enter. I 

 have had the entrances of several hives 

 closed for weeks at a time, without serious 

 inconvenience to the inmates, but I know 

 the connections were not air tight. Even if 

 they had been, the bees would have received 

 a considerable quantity of air through the 

 walls of the hive. 



It is a well established fact that atmos- 

 pheric air freely penetrates the tissues of 

 all plants. Core winder found that a single 

 colza plant, in 12 hours, decomposed 2 qts. 

 of carbolic acid gas. Bousingault found 

 that 12 square feet of oleander leaves 

 decomposed about the same quantity.— 

 These results prove that a very large quan- 

 tity of air must have coursed through the 

 plant. Some idea of the size of the " breath- 

 mg pores," or stomata may be formed, 

 when it is known that 100,000 of these open- 

 ings may be counted upon an average sized 

 apple leaf. Although the leaves are much 

 more pervious than the stems, air in various 

 degrees of purity may be found in all parts 

 of the plant. If green wood allows the free 

 passage of air, certainly dry wood will be 

 more pervious. We all know how freely 

 wood imbibes water, and it is safe to say 

 that air will go wherever water can, for it 

 is 770 times lighter. On the supposition 

 that one-half as much air passes through an 

 unpainted inch board as through a lime- 

 stone wall, well laid in morter, (not an 

 extravagant supposition, I think you will 

 say), I find by computation, that with the 

 size of hive we use, so long as the hive 

 walls remain dry, quite a large per centage 

 of the air required by the bees in winter 

 will enter this way. In proportion as the 

 wood hive becomes saturated with water is 

 the passage of air impeded, a fact of much 

 importance in wintering. 



How about the bees buried ? Facts are 

 on record, showing that men have been 

 buried for days at a time and were not suf- 

 focated. Certainly, when men can live, 

 bees ought to, as they require so much less 

 air. But the men were not buried under 

 frozen ground, you say. Von Rettenkoffer, 

 than whom there is no better authority living, 

 says that he believes frozen soil to be not 

 much less impervious to air than the same 

 soil unfrozen. I have not space to give his 



reasons, and will only say that he seems to 

 have the best of the argument. He says, in 

 regard to the free passage of air tlirough the 

 ground, " I know cases where persons were 

 poisoned and killed by gas, which had to 

 travel 20 feet under the street, and then 

 through the foundations, cellar, vaults and 

 flooring of the ground floor rooms." 



In wintering bees underground, we need 

 not have so much fear that the quantity of 

 air will fall short, as that it will be deficient 

 in quality. A year ago, in reading Prof. 

 Johnson's admirable treatise on "How 

 Crops Feed," I learned of the impurity of 

 the soil air. It usually contains all the 

 moisture it will hold, and from 10 to 390 

 times as much carbolic acid gas as the free 

 atmosphere. In sandy soil the air is the 

 purest. 



To keep the soil air out of our bee cellars, 

 last fall, we carefully coated the sides and 

 bottom with hydraulic cement, and I find 

 that it makes them much dryer and better. 



The material of which your bee house is 

 built will influence the amount of artificial 

 ventilation needed. In order to give you an 

 idea of the extent of natural ventilation 

 through the walls of buildings, I cannot 

 do better than again quote Rettenkott'er : — 



" For every square yard of wall surface, 

 at Q}4° f ahr. difference of temperature, the 

 spontaneous ventilation, or passage of air 

 through the wall, amounts per hour to 



4.7 cubit feet, with walls of sandstone, 



6.5 " " " quarried llmeatone, 



7.9 brick, 



14.4 " " " mud." 



We prefer to build our wintering houses 

 of earth. You would at first conclude that 

 sandstone walls would be more porous than 

 limestone, but sandstone is a smoother 

 stone and does not re(iuir(^ so much mortar. 

 It is the mortar that admits the larger part 

 of the air. There has always been a serious 

 disagreement between theoretical and prac- 

 tical ventilation, until a consideration of 

 the extent of natural ventilation reconciled 

 the difference. Many interesting experi- 

 ments are on record. With suitable appar- 

 atus, candles are extinguished by air blown 

 from the mouth through solid brick walls, a 

 foot in thickness. 



Another mistake still current in some of 

 our text books on ventilation is the state- 

 ment that impure air, being heavier than 

 pure, falls to the bottom of a room and 

 remains there, unless provision is made for 

 its outlet at that point. These authors are 

 ignorant of the law of the diffusion of gases. 

 Gases intermingle perfectly, no matter 

 what the variation in density. Usually 

 there is not much difference in the purity 

 of the atmosphere in the various parts of a 

 room, unless the changes are quite rapid. 



A consideration of the moisture of the air, 

 as well as of the practical appliances for 

 ventilation must be deferred for the pres- 

 ent. S. H. Elwood. 



Starkville, N. Y., Feb. 1, 1876. 



Mr. Editor:— The publication of this 

 essay has been postponed with the expecta- 

 tion of reviewing and correcting it. — 

 Further changes will be made in our venti- 

 lating apparatus, and I prefer to test thor- 

 oughly before recommending. S. H. E. 



June 1, 1878. 



