Chi PRACTICE OF AGRICULTURE. Part III. 



in length, the pita or stacks ore usually formed in this manner : —A spot adapted to the 

 purpose, of from about fifteen or twenty feet in diameter, of a conical Conn, is selected, 

 and after being properlj levelled, a large billet of wood, split across at one end, and 



pointed at the other, is fixed in the centre of the area, with its pointed extremity in the 

 earth, and two piece-, of wood, inserted through the clefts of t lie other end, forming four 

 righl angles; against these cross-pieces, four other billets of wood are placed, one end 

 on the -round, and the other leaning against the angles. A number of large and straight 

 billets are afterwards laid on the ground, to form a floor, each being, as it were, the 

 radius of the circular area; on this lloor, a proper quantity of brush or small wood is 

 strewed, to till up the interstices, when the floor "ill be complete: and in order to keep 

 the billets in the same position in which they were first arranged, pegs or stumps are 

 driven into the ground, in the circumference of the circle, about a foot distant from one 

 another; upon this floor a stage is built, with billets set upon one end, somewhat in- 

 clining towards the central billet, and on the tops of these another floor is laid, in a 

 horizontal direction, but of shorter billets, as the whole is intended, when finished, to 

 form a cone. The pile is then coated over with turf, and the surface generally plastered 

 with a mixture of earth and charcoal dust. 



4067. Previously to the operation of setting Jire to the pile, the central billet in the 

 upper sta^e is drawn out, and pieces of dry combustible wood substituted in its place, 

 to which the lire is applied. Great attention is necessary during the process, in the 

 proper management of the fire, and in immediately covering up the apertures through 

 which the flame obtrudes itself, until the operation be concluded, which is generally 

 effected in the space of two or three days, according to circumstances. vT hen the char- 

 coal is thought to be sufficiently burnt, which is easily known from the appearance of 

 the smoke, and the flames no longer issuing with impetuosity through the vents, all the 

 apertures are to be closed up very carefully, with a mixture of earth and charcoal dust, 

 which, by excluding all access of the external air, prevents the coal from being any 

 further consumed, and the fire goes out of itself. In this condition it is suffered to 

 remain, till the whole is sufficiently cooled ; when the cover is removed, and the charcoal 

 is taken away. If the whole process is skilfully managed, the coals will exactly retain 

 the figure of the pieces of wood : some are said to have been so dexterous as to char an 

 arrow without altering even the figure of the feather. (Encyc. Brit. vol. v. art. Charcoal.) 

 4068. The method of charring wood, for the making of gunpowder, according to an improved system, 

 adopted not many years ago, is however a much more costly operation, though the expense attending it 

 is amply compensated by the superior excellence of the article when manufactured. It is done in iron 

 cylinders, and in so complete a manner, that every particle of the wood is charred. The oily or tarry 

 nutter is also preserved, and may, so far as the quantity goes, be made use of instead of foreign tar or 

 pitch. This mode of charring wood for making gunpowder is carried to the greatest perfection near 

 Petworth in Sussex, and there is a manufacture of a similar nature near Chester. [Gen. Hep. for Scot- 

 land, vol ii. p. 342.) 



Sect. IX. Estimating the Value of Plantations and their Products, and exposing them to Sale. 



4069. The vahiation of timber forms a distinct profession, and can only be acquired by 

 continued observation and experience: like other valuations of property, it depends on 

 a great variety of considerations, some of a general, but the greater part of a local 

 nature. We have already ottered some remarks on valuing young plantations, as a 

 part of what may be called the inherent value of landed estates (3380.;, and shall here 

 confine ourselves to the valuation of saleable trees. 



4070. /" valuing saleable trees of any kind, their number per acre or their total number 



by enumeration being ascertained, and the kinds and sizes classed, then each class is to 



be estimated according to its worth as timber, fence-wood, fuel, bark, &C 



4071. In a coppice wood which cannot readily he measured, " the readiest method of counting the stools 

 is, to cause two men to take a line, say about a hundred feet long or more, and pass it round as many of 

 the Stools as it will enclose, the one man standing while the other moves round a new number of stools : 

 then count always the stools betwixt the two lines, causing the one man to move while the other stands 

 si ill. and so on alternately. The valuator at the same time taking care to average every twenty stools 

 as they go on, before losing sight of the counted stools. This way, too, is a very speedy and sure method 

 of counting the number of trees in any plantation." 



IfflS. <'r !!„■ stools of a coppice ivofd map In- counted and avoaged "by two men going parallel to each 

 other, and the person valuing going betwixt them ; the two men putting up marks with moss, or pieces 

 of while paper, on a branch of the Stools j the one man always going back by the last laid marks, and the 

 valuator always counting and averaging the stools betwixt the newly laid and the late made marks; 

 ((Hinting and averaging the stools always as the men go on, taking only twenty, or even ten stools 

 at a time. To those who have been in the practice of doing this frequently, it will be round very 

 easy, ami will be done very speedily, and with a \ er\ considerable degree of accuracy. The proper 

 method Of learning to do this correctly is, when a person cuts an oak wood for the first time or. even 

 were the work repeated several times ; he should then, in order to make himself perfectly acquainted 

 with ascertaining the Quantity of bark that a stool, or even the stump of a stool, will produce, go before 



. ° . .^ . . ... ,. i :i I.. 1 ... , — . :* *■« ....... 1>t. >n ■> 



from a natural stool, suppose it to measure in girth two inches, by seven feet long, will contain two solid 



inches, and one third of an inch, according to the measurement of Hoppus. Tins stem or shoot will pro- 

 duce I wo pounds two ounces of bark. Again, a stem or shoot of natural oak, measuring lour inches in 



