Vol. X. -No. 21. 



ANi> HORTICULTURAL JOURNAL. 



163 



quite iniitlcqii.itLi to proiluce such an cfl'ect. Bui, when 

 revived wiiii less pietensioti, steam was found to be a 

 couvenient ami economical mode ofdistiibuliug iieat.* 



Loudoti says, ' Pipes of hot water have been proposed 

 to be circiil.ited through hot houses by Knight, {Hort. 

 Trans, vol. iii); tiie plan was Irieti many years ago by 

 the late GouM, gardener to Prince Potemkin, in the im- 

 fnense conscrvalocy of liie Taujidian palace at Peters- 

 burgh.' — Enc. o] Gard. p. 32S. 



The advantage to be derived from heating hot houses 

 by hot water is the consequence of the great capacity of 

 water lor heat. Suppose a gallon of water was heated 

 to 212 degvees, the boiling point, an. I a «;allon of air was 

 «Iso heated to the same temperature. The water would 

 contain, according to the lowest estimate, (for philoso- 

 phers are not perfectly agreed on this subject.) _^wfi hun- 

 dred times as much heat as the air. If the water and 

 the air, when so heated, were each of them confined in 

 timilar water light and air tight vessels, in contact with 

 as much ice as each could melt in cooling, the hot water 

 would be found to have melted at least five htindred 

 times as much ice as the hot air. Water too, when heat- 

 ed, will be at least as much longer in cooling than air, of 

 the same temperature, as it contains more caloi-ic. 



• Water,' says an eminent philosopher, 'appears to pos- 

 sess the greatest capacity for heat of any pure liquid yet 

 known, whcih.:r it be compared with equal bulks or 

 weights; indeed it may be doubted whether any solid or 

 liquid whatever contains more heat than an equal bulk 

 of water of the same temperature. The great capacity 

 of water arises from the strong affinity, which both its 

 alements, hydiogen and oxygen, have for heat Hence 

 it is that solutions of salts in water, contain generally le<s 

 heat in a given volume than pure water; for salts in- 

 crease the volume of water, as well as the density, and 

 having mostly a smaller capacity for heat, they enlarge 

 the volume of water more than proportional to the beat 

 they contribute.'* 



It is, however, remarked by Mr Tredgold, that the 

 boiling points of solutions of salt and some other liquids 

 are higher than the boiling point of water. Linseed oil, 

 for instance, will not boil until it is heated 600 degrees, 

 or made almost three times as hot as boiling waler. Con- 

 requenlly we should need only one third as much sur- 

 face of pipe, and one third the capacity of boiler and 

 reservoir lor heating a given space with boiling oil as 

 with boiling water. But solutions of salts are corrosive, 

 and oil very inflammable, as Mr Tredgold correctly ob- 

 serves. On the whole, we believe there is nothing like 

 water to seize and retain the heat produced by combus- 

 tion, and prevent its escape into the open air before it 

 has been subservient to any purpose of economy. — 

 Steam is an excellent agent to carry ami distribute beat. 

 ■ With the help ol a little skill in its management, it will 

 go where you bid it, and leave its commodity ol caloric 

 where most needed. But it carries but little heat at a 

 load, in proportion to its bulk and temperature. It re- 

 quires large surfaces of pipes or other receivers, in pro- 

 portion to the space it warms. And iri a few minutes 

 after the fire which creates it slackens or is extinguish- 

 ed, the vessels it filled become as cold as the air which 

 surrounds them. Hot water carries and distributes much 

 more heat than steam in proportion to its bulk and tem- 

 perature, requires less appara'us, and heated surface for 

 emanating a givn quintily of lieat, and will caniinue 

 to give out warmlh for hours after its supplies from th 

 &re place are cut off. But it must be dealt wilh accord-j 

 ing to the laws of hydraulics and hydrostatics, and though 

 more efficient when it begins to act, is not so readily 

 brought into action as steam. 



Willi regard to large boilers, and large reservoirs, 

 which Mr Perkins says are objected to, ^ve can say noth- 

 ing either from Oiir own experiments, or Iroin personal 

 observation ; and shall merely give the opinions of such 

 writers as we have been able to consult ; together with 

 some remarks, founded on analogy, and the little experi- 

 ence we have derived from a poitable app.iralus, which 

 we call a Steam and Hot Water Stove, (lor which the 

 writer has obtained letters patent,) for healing ajiart- 

 ments, &c, by the agency of hot water and steam. In ad- 

 dition to what Mr Tredgold observed, (as quoted above 

 by Ml' Perkins,) in favor of a large boiler, 'as a reservoir 

 ol heat, to act when the fire ceases to burn," it may be 

 slated that the experiments of Count Ruinford, {Essay 

 vi. ch.ip. V.) are in favor of large boilers. For, in order 

 to keep 508 pounds of water boiling, the expenditure of 

 fuel by the tiour was something short of one eighteenth 

 part of the weight ol the water ; whereas, in a smaller 

 boiler, holding only 284 pounds of water, the expenditure 

 of fuel was more than one twellth part of the water. — 

 Mr Tredgold judiciously observes that 'the bottom of 

 the boiler should have sufficient extent of surface to re- 

 ceive all the force of the fire, as far as the heat of it is 

 capable of being extended, so as not to be less than 212 

 degrees; a greater surface will not generate steam ; a 

 less will not produce the greatest effect. And it is clearly 

 a disadvantage to suffer the smoke of the fire to come in 

 coi tact with the boiler after its heat is less than ihat ol 

 boiling water ; for if it be continued in contact with the 

 boiler, it will rob it of heat instead of adding to the ef- 

 fect of the fire. ' 



If the boiler is less than the reservoir, its perpendicular 

 height should be at least as great, in order to insure the 

 quick circulation of the fluid. , 



Mr Tredgold says, ' all other things being the same 

 the velocity will be increased in proportion to the square 

 root of the depth of the boiler ; therefore in a boiler four 

 times as deep the velocity would be doul>led.'t 



Among the several plans, which Mr Tredgold has giv- 

 en as impiovements on Mr Atkinson's, we should prefer 

 the one sketched above by Mr Perkins, with this altera- 

 tion, which might not however be an improvement.— 

 Tlie reservoir we would make much larger, in propor- 

 tion to the boiler, than is there represeuted. We would 

 do this because all water, however low its temperature 

 may be, contains a large portion of caloric. A large 

 quantity of waler drawn from a well or taken fiom a 

 spring in the winter time, and placed in open vessels in 

 a cellar, not subject to frost, generally protects vegeta- 

 bles, &c, from being frozen. This is a fact known and 

 practised upon by many a good housewife, whose philo- 

 sophy never dreamt of the cause. This we will briefly 

 explain. Water at the mean temperature of this climate 

 contains more than 20 degrees of heal, which it must 

 gVe out before it can freeze, and while freezing, it gives 

 oit 140 degrees, according to Dr Black. This heat i» 

 yielded to surrounding objects, including the vegetables, 

 4c, in the cellar, which keeps the lempeiature above 

 tlie freezing point of 32 degrees, till the water is frozen 

 ind can give no more heat. The vegetables, &.C, will 

 then freeze if the weather continues sufficiently cold, 

 and no other supply of caloric is provided. We see no 

 reason to dissent from the other statements of Mr Per- 

 kins, whose remarks appear to us judicious and scientific. 



We hope the importance of the subject will apologize 

 for the length of this article; and intend to lesuiiie the 

 discu.ssion as soon as our avocations and pre-enoagements 

 will possibly permit. 



^ Dallon'i Ctiemictil Philosophy. 



• Tredgold on Warming and Ventilating Roomi, p. 163. 

 f Hot. Trani. vol. vii. p. 575. 



VARIETIES OF OAKS. 

 Mr J. B. P.ussELL — 



Dear Sir— Observing in your paper that several 

 persona have been forwarding Jtcorns, for a collec- 

 tion to be sent to the Horticultural Society of Lon- 

 don, I take the iiberly of inclosing you, herewith 

 the list, or catalogue, of those which I have put up' 

 already this season, and forwarded to that Society, 

 by the ship Fanny, from this port. They were all 

 collected this fall, from this garden, and the imme- 

 diate vicinity ; and several other sorts, which failed 

 to bear seeds, this year, will be sent to that society 

 next fall. We always collect our acorns, and other 

 seeds, from the purest standard plants, .iiid do not 

 collect them in the woods, nor purchase them from 

 others, unless they are gathered from trees which 

 we point out. Of the Oaks, in our woods, the mix- 

 tures, or hybrids, are infinite ; I can collect 11 or 12 

 different sorts of acorns of the (^uercus alba, and 

 quite as miny of the Q. tinctoria. Of the former 

 we have here one tree which produces blue acorns ; 



but that is owing to a diseased state of the tree. 



Many of the trees, in this old garden, are the iden- 

 tical trees figured and described by the Michauxa, 

 (father and son,) and by F. Piirsh, all of whom made 

 this place their residence, whibj in this neighbor- 

 hood. KespectfuUy, yours, 



Robert Carr, 



liartrnm Botanic Garden, 1 

 rijiladelphiii, Dec.3, 1831. j 



CATALOGUE OF THE ACORH3 



Of A'orth ..American Oaks, sent from the Bartram Bo- 

 tanic Garden, near Philadelphia, to the Horticultural 

 Society of London, JVov. 1831. 

 [Tlio names arc according to ' Pursh's Flora of North America '] 



1. Quercusalba White Oak. 



2. " phellos. Willow Oak. 



3. " heterophylla. Bartram Oak, of Michaux. 



4. " aquatica. Water Oak. 



5. " nigra. Barren Oak, or Bl?ck Jack. 



6. " " A variety of do. 



7. " tinctoria. Black Oak, or Quercitron. 



8. " " A variety of do. 



9. " discolor, or Q. tinctoria sinuosa, o( Mi- 



chaux. 



10. " " A variety of do. 



11. " coccinea. Sciirlet Oak. 



12. " " A variety of do. 



13- " rubra. Red Oak, or Champaign Oak. 



14. *' " A variet)' of do. 



l.";. " falcata. Spanish O.ik; also called Red 



Oak in some of the South- 

 ern States. 



16. " " A variety of do. 



17. " palustris. Swamp Spanish, or Piu Oak. 



18. " " A variety of do. 



19. " banisleri. Bear Oak, Black Scrub Oak, 



orDwarlRed Oak. 



20. " obtu.siloba. Upland White Oak, PostOak, 



or Iron Oak. 



21. •' macrocarpa. Over-cup White Oak. 



22. " lyrata. Over-cup Oak, Swamp Post 



Oak, or Water White Oak. 



23. " monlana. Rock Chesnut Oak. 



24. " bicolor. Swamp White Oak. 



25. " sericea. (Q. pumila, of Michaux,) 



Running Oak. 



26. " chinquapin. Dwarf Chesnut Oak. 



JVaturnlisalion. — Since the discovery of the New 

 World, our English gardens have received 2,345 

 varieties of trees and plants from America, and up- 

 wards of 1,700 from the Cape of Good Hope, in ad- 

 dition to many thousand which have been brought 

 from China, the East Indies, New Holland, various 

 parts of Africa, Asia, and Europe, until the list of 

 plants now cultivated in this country exceeds 120,- 

 000 varieties. — London Mlns. 



Sheep in Vertnont. — It is estimated that there are 

 766,803 sheep in Vermont The several counties contaiu 

 as follows :— Bennington 52,416, Windham 55,542, Rut- 

 land 139,9!)l), Windsor 109,787, Addison 112,787, Orange 

 73,155, Chittenden 55,449, Washington 40,856, Caledoni* 

 43,748, Franklin 41,638, Orleans 23,797, Essex 6,976, 

 Grand Isle 8,656. 



