501 



JOUENAL OF HOBTIOULTUEE AND COTTAGE GAEDENEE. 



C December 25, 187S. 



coke, will in the future, as at present, be the great heating 

 power, and on these I shall remark separately as they appear 

 suited or otherwise for the heating of horticultural structures. 



Coal. — The heating power of this not being equal to gas or 

 coke, though it is contended by some that " coke is but coal 

 minus its virtue " — i.e., gas ; and because coal is used in the 

 furnaces of locomotive and stationary engines, as weU as for 

 other purposes for which coke was only a few years ago em- 

 ployed, from its being considered to have a greater heating 

 power, it has been concluded that as it is used for pur- 

 poses for which coke was formerly employed, coal must neces- 

 sarily be superior. It seems to he altogether overlooked that 

 coal is cheaper from being the material from which coke is 

 made, therefore entailing no cost of manufacture, and owing 

 to its taking up less room being easier of transit. Besides, 

 coal as used in most engine furnaces is so consumed that the 

 smoke is also burnt, the gas not wasted, and therefore in this 

 case coal may have a gi-eater heating power than coke. It is 

 entirely different with our hotwater boilers. None that I 

 know are smoke and gas consuming, or, at least, a portion 

 only of the gas is consumed, the rest escaping with the smoke 

 up the chimney. Coal as used in hot-water boiler furnaces is 

 not so efficient nor so economical as coke; such, at least, has 

 been my experience. When coal is used the surface of the 

 boiler soon becomes coated with soot, and this forms one of 

 the worst barriers to keep the heat of the fire from the water 

 in the boiler. How it would be were the smoke consumed is 

 another matter. Hot-water boilers, as well as those for the 

 generation of steam, ought to consume in their furnaces the 

 smoke resulting from the combustion of coal or other fuel. 

 Until this is the case, the fire acting directly instead of, as at 

 present, indirectly through a coating of soot on the boiler 

 surfaces, I cannot admit coal, with its " virtne," to be so 

 great in heating power as coke, especially as experience has 

 shown me the contrary. Besides, it is absurd to have the 

 chaicosl of coal — that is, coke, of less heating power than coal, 

 charcoal having more than double the heating power of wood, 

 and turf charcoal double that of the turf from which it has 

 been produced. 



A boiler that will consume coal, coke, or wood may be a 

 desideratum with some. I have not seen a boiler furnace that 

 would not consume any or all of these substances, but they do 

 not do so with the same result. Some, as the upright tubular- 

 boiler furnaces, are not suitable for consuming small or slack 

 coal, though they burn a mixture of small coal and coke, or 

 cinder, very well. The horizontal boilers, or rather their 

 furnaces, will consume anything, and I have often put their 

 capacities in this respect to the test ; but then boilers which 

 consume all kinds of fuel are, as a rule, possessed of no great 

 heating power, and as an exception to the general nm of 

 boilers, may safely be excluded as calling for any special 

 remarks, for all boilers ought to have sufHoient draught which 

 can be regulated to consume every description of combustible 

 matter. 



Coke is in most instances a superior fuel to coal, but as 

 some of our boiler-furnaces are constructed, and so ill-pro- 

 vided for insuring a draught, they do not hold a sufficient 

 quantity of it nor of air to insure free ignition and thorough 

 combustion ; but where they are properly constructed I have 

 not found coal equal to coke in heating power, nor so economical. 

 Coke does not give-off smoke, the surfaces of the boiler do not 

 become coated with soot, the heat of the fire has consequently 

 full play on the boiler's surface ; the heat does not pass along 

 the flues to the chimney, but is absorbed by the water inside, 

 and is, in fact, all heat ; whilst coal has a black surface for 

 a long time after feeding, and the smoke and the gas 

 liberated along with it are often not consumed. If the gas be 

 not consumed (and when the fire has a dull surface it is not, 

 as it cannot be ignited without contact with flame or great 

 heat), it must be lost, and on this account I contend it would 

 be more economical to take from coal its gas, employing it 

 with coke, but separately, for the same heating purposes as coal 

 now is, and I am sanguine enough to consider that the heating 

 power would be doubled, or, in other words, double the heat 

 would be obtained that is at present secured. — G. Abbey, 



PANSY BLUE KING. 



In your issue of the 4th inst. there is a descriptive list of 



bedding Pansies by Mr. Shenton, where he describes Blue 



King as of " rather a straggling habit, a late bloomer, and a 



variety that will not stand the sun well.'' The Blue King of 



Hale Farm Nurseries must be a very different and much in- 

 ferior variety to the Blue King of Stanstead Park Nurseries 

 (the true Blue King), as here it begins flowering very early in 

 the season, and continues to bloom profusely throughout the 

 spring and summer months, and very late into the autumn — in 

 fact, it is almost perpetually in bloom, having commenced 

 flowering at the beginning of last March and continued in 

 flower ever since (it is in bloom now). It is a splendid blue, 

 of good substance, and as a mass there is no other blue bedding 

 Pansy to compai'e with it. Mr. Shenton has evidently grown 

 a spurious variety. — E. B. Weight. 



ORNAMENTAL PLANTING.— No. 13. 



Almost all kinds of trees and shrubs may be removed with 

 much less risk of failure than would otherwise be the case, 

 and become more quickly established, by a judicious use of 

 the pruning knife, sometimes to the roots, and sometimes 

 to the branches — to the roots when the tree has remained 

 stationaiy sufficiently long for them to become " lusty, stout, 

 and strong," with very few fibres near the bole. It is there- 

 fore necessary to cut asunder all the large roots one year before 

 the removal, putting sufficient rich goU about the whole of 

 them to induce the formation of abundant fibres, staying the 

 tree with wires to prevent its being blown over; then, when 

 it is lifted in the following season, the ball is one mass of 

 hungry mouths that quickly seize upon the fresh soU, spread- 

 ing in it with surprising vigour and rapidity. The knife may 

 be used to the branches at the time of removal, in order to 

 shorten all long, slender, or immatm'e growth so as to check 

 excessive evaporation, and to lessen that strain upon the system 

 which so frequently proves fatal. 



This pruning of both kinds is so important and invariably 

 beneficial that it may be well to explain somewhat more fully 

 why it is so. Although our present knowledge of the meanings 

 and uses of the various organs in vegetable physiology is 

 imperfect, yet we do know that the vitality of a tree principally 

 depends upon a healthy and vigorous root action. When a 

 shrub is transplanted it sustains a certain shock or check, the 

 effects of which are precisely in proportion to the plant's fit- 

 ness for and the manner of its removal. As has been already 

 stated this fitness consists in its having numerous rootlets and 

 fibres upon the roots that are nearest the stem, so that as 

 many of them may be retained as possible, and the chief aim 

 of the planter is to transplant it so carefully that the roots as 

 well as the branches may sustain no damage. Then when the 

 soft temperature of spring induces fresh growth nothing is 

 wrong in the economy of the plant, no wasted growth nor 

 exhausted tissue ensues, but all is in readiness for its natural 

 requirements during the season of growth — the roots very 

 frequently being already spreading in the fresh soil, thus the 

 sap out of which every part of it is formed is abundantly 

 supplied to every swelling bud, and brauchlet, and leaf, and it 

 is to insure this that the tips of any long branches are pruned 

 off. But this is not always necessary, and when there is no 

 risk of drooping or exhaustion, it is generally best to retain 

 them intact. 



The treatment of the roots cannot be too tender, no turf or 

 flowers should be suffered to exhaust the soil near them for the 

 first two or three years, nor should it be subjected to the effects 

 of drought, or frost, or even become water-logged. 



A word or two more in reference to the plan of a portion of 

 shrubbery border in page 19. The shrubs in the front row 

 should be G feet apart, increasing the distance to 9 feet for 

 those of larger growth in the next row, and to 1'2 feet for the 

 occupants of the third row, which last distance would be 

 ample for the trees of the sheltering belt behind. — Edwaed 



LUCKHUEST. 



PEIMEOSES AND POLYANTHUSES. 

 I HAVE more than once had my attention drawn to the fact 

 that thrum-eyed Polyanthuses do sometimes change to pin- 

 eyed. This I have only found in seedlings of the first year ; 

 but I have no recollection of an established flower changing 

 its character in that respect. Two or three times last season 

 I was especially puzzled by some plants of Pantaloon Polyan- 

 thus, which were labelled the previous year as being thrum- 

 eyed, proving to be pin-eyed and vice versa. This winter a 

 fine large-flowered common Primrose which I took from the 

 woods, and which has been labelled thrum-eyed for the last 

 two years, has just flowered with a pin-eyed flower. I can 



