254 



JOURNAL OF HOBTICULTUEE AND COTTAGE GARDENER. 



[ March 2G, 1874. 



of it, and the hothouBBB and Vine borders must not be over- 

 looked. It will always be useful to have a plan of the whole 

 arrangement drawn to a scale, and with all important points 

 and outlets marked on it for future reference, in case of alter- 

 ations and repairs being found necessary. Where it can be 

 done I should prefer separate drainage for the glass houses 

 and Vine borders, on account of the extra watering the Vines 

 would need, and the more general and constant use of water 

 in those places ; so that, if any misfortune befell the drains 

 in the garden it would not affect those of the hothouses. 



I will now offer a few remarks upon the materials of which 

 drains are composed, and which are various, such as stones, 

 brickbats, fiints, chalk in large pieces, and sometimes wood. 

 The above are, perhaps, more suitable for collecting the water 

 than for carrying it off, and one reason for using them is that 

 they can in many cases be more easily procured than other 

 things. In districts, for instance, where stones abound the 

 excavations for foundations consequent on the formation 

 of new gardens often afford enough to supply all the drains 

 and to serve for many other purposes. Stone is the most 

 lasting of any material ; nevertheless, tile or pipe-draining 

 is most resorted to in these days, and the pipes used are 

 of various sizes, according to the nature of the soil and the 

 probable quantity of water which will have to pass through 

 them. I do not recommend having them too large for garden 

 drainage. They are made in lengths of a foot or 15 inches, 

 and from 2 to 4 inches in diameter, the smaller size being used 

 for the branch drains and the larger for carrying the water 

 away. I ought to have said, that when laying the drains in 

 the garden in connection with the walks their course should be 

 marked out by stakes, so that when the walks are made and 

 drained there will be no difficulty in finding the lower drains 

 for the purpose of connecting the others to them. 



After draining comes trenching, which is an important ope- 

 ration for the pulverisation and improvement of the soil ; but 

 on a new piece of ground that has become hardened by lying 

 undisturbed for years, it is not only necessary to consider the 

 best method of trenching it up, but also whether it will be 

 advisable to do it at all for the first year or two, at least to 

 any great depth ; because in some oases — hungry clays or poor 

 gravel, for instance — the subsoil is even worse than that at the 

 top, and if turned up it would be quite unworkable and UBfer- 

 tile for years. I should prefer to treat this differently, by merely 

 turning the ground over a good spit deep, breaking up the 

 bottom 6 inches, and at the same time adding some manure 

 or better soil. After two or three crops had been taken off I 

 would trench it up another spit deep, still keeping the surface 

 soil at the top ; and when the subsoil had become more work- 

 able and pulverised I would trench it up again at the same 

 depth, but this time turning the bottom spit to the top. If it 

 could be arranged for this to be done in winter the soil would 

 work all the better in the spring. I have practised this method, 

 find have found it a very safe one to recommend. It may be 

 taken as a rule that on most plots of land there is a surface 

 soil of greater or less thickness, possessing far greater produc- 

 tive qualities than that lying beneath it, and to trench this in 

 to 2 or 3 feet in depth seems to me bad policy. 



There is, however, another way of going to work which may 

 be here stated, and that is to turn up the ground three spits 

 deep, leaving the bottom one there, placing the top spit in the 

 middle, and mixing with that and the top one what refreshing 

 soil or manure the ground may seem to be in need of. On 

 the other hand, where a soil is to be found of good quality to 

 a uniform depth of 3 feet, the case is so different that I have 

 no hesitation in saying that this may very advantageously be 

 trenched to the full depth at once. It may be that the spot 

 chosen for a garden has an exhausted surface soil ; here, then, 

 is a good reason why trencliing should be done at once, but 

 even then I should be careful not to break-up the ground too 

 deeply for one year. Of course, all hardened soils when re- 

 quired for gardening purposes must be broken up, and are 

 benefited thereby, and I have thrown out the above hints for 

 the purpose of showing how necessary it is to make a careful 

 examination of the soil before going too far. I once took 

 charge of a garden which had been formed out of a meadow, 

 and possessing from a foot to 18 inches of good loamy soil on 

 the surface, with a subsoil approaching a clay. The trenching 

 was done at the same time as the draining, and all the good 

 soil was deposited at the bottom. I have known a man labour 

 hard a whole day to work-down the soil and sow two row.s 

 of Peas ; this was in dry weather when the soil had become 

 hardened by the sun, but in wet weather the operation of 



working it down was equally difficult, it being so tough. Most 

 of the ground was retrenched so as to bring the old soil to the 

 surface again, and this proved to be a successful operation, for 

 the crops grew better and the labour of the garden was much 

 less difficult, though the good soil had become somewhat 

 deteriorated owing to the garden being insufficiently and too 

 deeply drained. — Thomas Eecobd. 



HEATING. 



I HAVE received a kindly letter, which gives me an opportunity 

 to state that, though fully aware of Mr. Hood's mode of cal- 

 culating the amount of piping required to secure any desired 

 temperature by the surface exposed — viz., IJ cubic foot for 

 every superficial foot of exposed glass surface, I did not adopt 

 it, as the finding is so fallacious and contrary to the require- 

 ments of practice as to lead me to the conclusion that Mr. 

 Hood intended the cubic contents of the structure to be taken 

 as the basis of calculation. This conclusion is, I think, borne 

 out by the table given by Mr. Hood in his treatise on " Warm- 

 ing BuUdings by Hot Water," showing the quantity of 4-inch 

 pipe which wiU be sufficient to heat 1000 cubic feet of air per 

 minute to from -15° to 90°. 



For example, to secure a temperature of G5° for 1000 cubic 

 feet of ah', the external air 40°, we have in the table 104 feet 

 required, and by Mr. Hood's rule (see page 181) very nearly a 

 corresponding result. 125 x 25 = 312.5 + 135 = 23 x 1000 = 23,000 

 + 222 = 103 feet of 4-inch pipe. Admitting, however, my being 

 in error, the cubic contents of the structure not being intended, 

 let us apply the rule to the stove alluded to at page 181. The 

 extent of glass surface is 1188 feet superficial, and we shall 

 have, at IJ cubic foot for every foot of exposed surface, 

 1485 cubic feet of air to be heated from 40°, the mean tem- 

 perature of the winter months in our climate to 65°, the 

 highest maximum from fire heat required. 125 x 25 = 3125 -i- 135 

 = 23 x 1485 == 34,155 + 222 = 153 feet of 4-inch piping, which 

 would be barely sufficient to keep out frost, much less to give 

 the required temperature of 65°, being less than one-third of 

 what is needed in practice. We have 4780 cubic feet of air 

 to heat, and only provide to heat 1485 ! What is to heat the 

 remaining 3295 cubic feet of air? Mr. Hood surely meant 

 the cubic contents of the house, adding IJ cubic foot for each 

 superficial foot of glass surface, which will give G49 feet of 

 4-inch piping ; or, if we take the cubic contents of the house, 

 we require 495 feet of piping, practice demanding 558 feet of 

 4-iuch pipe, or six rows all round excepting doorways. I 

 therefore concluded Mr. Hood intended the cubic contents, a 

 conclusion I do not depart from ; and as Mr. Kinnear courts 

 criticism, allow me to apply the formula given at page 167 to 

 the stove above alluded to, C5° the temperature of the struc- 

 ture and 40° the external air. The superficies 1188 mnltiphed 

 by eleven times the intended difference 25°, and the product 

 divided by fifteen times the intended difference of the heat of 

 the water (200°) and the air of the house (05°) gives us 161 feet 

 of 4-inch piping. Let us take the cubic contents of the struc- 

 ture 4780 cubic feet ; following Mr. Kinnear we obtain 649 feet 

 of surface at 200° to give the temperature required, which is 

 very close upon what practice demands, and is a most excellent 

 mode of calculating the piping required. 



I make no complaint against the theoretical calculations. 

 Mr. Kinnear knows full well that no one keeps the heated 

 surface regularly at 200°, the water being that at night may bo 

 not half that in the morning ; therefore, to meet this loss we 

 need in practice considerably more heated surface to give U3 

 the required temperature just because we do not keep the 

 heating surface at its maximum constantly, it being on an 

 average not more than half the temperature it is theoretically 

 calculated to be. 



Permit me to thank Mr. Kinnear for his very able papers, 

 which have deeply interested and instructed me, as also no 

 doubt many of your readers. They are very valuable were it 

 only that they showed what a waste of coal takes place in our 

 stokeholes. — G. Abeet. 



KnoDODE^jBRON Show.— The Commissioners of EusaeU Sijuar© 

 have given permission to Messrs. John Waterer <fc Sons, of Bag- 

 shot, during the month of June next, to hold their Exhibition 

 of lihododendrons in the garden of that square. The garden is 

 one of the largest and best kept in London, and it is in a good 

 position, and adapted for a display of this kind. We are in- 

 formed that the Exhibition will be on a very large scale, and 



