Acre of Land, on the System recommended by Mr Withers, and that generally adopted by the Scotch Planters."

This table we shall give as nearly as our limits will allow, in its original form. It is partly founded on tables by Mr Waistell, respecting the growth of timber, published in the 26th volume of the Transactions of the Society of Arts. The height of the tree is taken to the top of the leading shoot; the circumference is taken half way up the tree, and no account is made of the lateral branches. What is termed the girt, is one-fourth of the circumference *. Estimates of the original expenditure under the two systems are thus given:

By the common practice of carpenters, all timber is considered as measurable in which the square of the girt, to use their own language, is 6 inches, or, in other words, in which a fourth part of the circumference of the tree where measured is 6 inches. Timber of a less size than this is not considered to be measurable. Honest Hoppus is the great authority in such cases, and his tables, we believe, are in general use: his rule is to take the length of the trunk, so far as it affords the necessary girt, to take a medium of the girt, to divide it by four, and multiply by the length. The same course is practised with such of the larger branches as possess the necessary girt. This rule, indeed, does not give the true contents of the tree, but it is sufficient for practice, since the mode is uniform, and prices are calculated conformably to it. Mr Waistell takes the length of the tree to the top of the leading shoot. He measures the tree at the base, and assumes it to be a regular cone from the base to the height of the highest shoot. He takes half the circumference at the base, or, which is the same thing, the circumference at half the height. He divides this by four, squares the result, and multiplies it by the length. This rule is not more geometrically correct than that of Hoppus, and is less conformable to practice. The effect is to make the cubical contents of Mr Withers' tables less than they would be by the common rule: thus the tree of 80 feet in height and 12 inches of mean girt, which Mr Withers calculates to contain 80 feet of timber, would, according to the rule of carpenters, contain 93 feet 9 inches of measurable timber, as it were easy to show.

Mr WITHERS'S Expenditure and PROFIT, reckoning the Annual Increase of the Trees to be Fifteen Inches in Height and One Inch and a Half in Circumference at the Base.

Expenditure and LOSS on the Scotch System, reckoning the Annual Increase to be Six Inches in Height, and Half an inch in Circumference.

"Since the publication of my Pamphlet," Mr Wither's adds, "I have received a great many communications relative to planting, most of them commendatory, but some expressing doubts of the benefits to be derived from the new mode of culture. One of the objections is, that the compound interest of the original outlay will be more than equivalent to the advantage arising from quick growth. The operation of compound interest cannot be known without calculation; and being desirous of ascertaining the probable efficacy of my mode of planting, and the validity of every objection to it, I formed a Profit and Loss Table of the Produce of One Acre of Land manured and planted, and the same quantity planted on the Scotch System, at the end of 64 years. As a foundation for my calculations, I took the tables of Mr Waistell, re-published with my pamphlet; and I did so because I knew of no other published statements of the produce of wood lands, and I trusted to his great experience for their correctness. He stated the average annual growth in healthy woods to be from 12 to 18 inches in height, with girt in proportion. My plantations have hitherto made a growth very far exceeding 18 inches; but in the table I anticipated a growth of 15 inches only on the average, and I took that of plantations on the worst system at 6 inches, a growth exceeding considerably that of many plantations with which I am well acquainted. I also allowed the same number of trees to live on both systems, although on mine the failures do not amount to five per cent., while, on the other, they certainly exceed fifty. I also reckoned upon thinning each plantation as recommended by Mr Waistell, so as to leave the trees at distances from each other equal to one-fifth of their height. I completed the table, and the results obtained were a gain per acre at compound interest on my plan of L. 6435: 8: 6, and an actual loss on the other of L. 152: 17:9. With a view of drawing public attention to so important a subject, I determined to publish the table immediately. A considerable number were actually printed, and orders sent for advertising it, when I received a letter from Sir Thomas Beevor (to whom I had sent a MS. copy of the table), in which he stated,

and proved to my satisfaction, that forest-trees could not grow to the estimated extent, nor without injuring each other, so closely together as Mr Waistell had allowed them. Sir Thomas's letter was accompanied by a table of distances, about twice the width of Mr W.'s, and founded on the actual measure of trees and their distance from each other at different ages. I therefore remodelled the table according to the alterations suggested by Sir Thomas; and thus improved, I now lay it before the public, confidently anticipating, that though a difference of opinion may exist as to the profit to be actually realized, enough is shown to prove, that a liberal expenditure in planting and subsequent management, with compound interest thereon, will be amply repaid by the increased growth of the trees thereby occasioned.

"The profit above shown exceeds the original expenditure, improved at compound interest at 5 per cent. for the whole period, by upwards of L. 500 an acre. Surely no capitalist can wish for a greater return than this for his money, or a more secure investment for it than his own land; but if a further inducement for planting be wanted, it is to be found in the gratification of giving profitable employment to those who are now wasting their time in idleness or on the public roads, morally degraded in themselves and burdensome to the community at large.

"Note added at the request of Sir Thomas Beevor.-It probably will be objected, that trees seldom arrive at the actual height contemplated by this table. It is a very fine tree which will mete 40 feet in length; but after a tree attains a certain state of maturity, instead of increasing in one continued shoot it diverges into large arms. These, provided they are allowed sufficient room to extend themselves, will cause an increase of timber fully equal to that which would have been obtained had the growth of the tree continued vertical. The figures of lengths, after the period alluded to, must therefore be considered only as modes of calculating a result which will be found to be practically true; viz. that the content of any tree at different periods, or of equally fast growing trees of different ages, are to each other as the cubes of their respective ages or periods of age."

The table, it will be seen, shows, that by the one mode of planting there will be standing on each acre at the end of 64 years, 40 trees 80 feet in height, and containing each 80 cubical feet of timber; that the whole value of trees, standing and cut down, will be L. 1181: 14: 9, and the whole profit derived L. 1305, 9s. 8d.; while, by the other mode of planting, the whole value of the trees standing and cut down will be L. 95, 11s., and the whole loss L. 273: 10:5.

Now, to this table there is this very obvious objection, inde pendently of those which may be shown to exist to the principle of calculation; namely, that it is not what it purports to be. It is not a comparison between the returns under two modes of planting, but a comparison between the returns under two assumed rates of growth in trees. It is assumed that in one

case trees will increase at the rate of 15 inches in height annually, and 14 inch in circumference; and in another case at the rate of 6 inches in height, and inch in circumference: And, further, that they will continue this difference of growth uniformly for 64 years. The postulates being granted, it is indeed easy to show, that in the one case there will be a great return to the planter, and in the other no return at all. But does Mr Withers not perceive that the table really proves nothing as regards the relative returns of two systems of planting? He calculates in one case on a return of 8162 cubic feet of timber,

Now, whether he assumes

in the other on a return of 2292 feet. all this, and reasons analytically, or whether he begins at the beginning, and reasons synthetically, the result is the same. He assumes what is really to be proved; namely, that in the one case above 8000, and in the other above 2000, cubical feet of timber will be produced in 64 years. Granting that the growth of trees is uniform (which it is not); that in 64 years they will reach the gigantic height of 80 feet (which they will rarely do); that their mode of growth is analogous to a gradually enlarging cone (which it never is), what does this prove as to the effects of muck and marl? Certainly nothing, if we found upon such experiments as Mr Withers records. Or granting that muck and marl will produce such effects, what does this prove as to the effects of a system where neither muck nor marl are employed? In the one case, we have presented to us an assumed case of successful planting, in the other an assumed case of failure in planting. Looking at the table itself, we find that at the age of 23 years the acre of land under the one system has produced 872 faggots of no value; at the age of 29 years 532 walking sticks, worth 2d. each; and at the mature age of 64 years, trees 4 inches in girt, and containing each 3 feet 6 inches of timber, worth 1s. the foot. The error in the conclusion shows, that the premises must be unsound. Trees which, in the period of 64 years, should produce only 34 feet of timber, worth 1s. the foot, would be reckoned a failure upon the most worthless soils; and on all tolerable soils would be grubbed up as useless, or burned as faggots, ere they attained a fourth part of the age assigned to them *.

The reader may have remarked certain errors in the details of these les: Thus, the land upon which wood is planted, is not annihilated by