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noticed that the winds were much lighter throughout the day than usual,
During this part of the year the atmosphere is clear, with a cloudless sky, and the coast is exempted from the violent E.S.E. squalls that are of frequent occurrence, while the sun is in the southern hemisphere, and the land consequently very much heated.
Towards the latter end of August, and in September, the winds are not quite so regular, and there are occasional intervals of two or three days of westerly winds.
That part of the north-west coast, between the north-west Cape and the 116th degree of east longitude, seems to be subject to westerly winds, at all times of the year. The prevailing southerly winds that blow along the west coast, appear to draw round the Cape, and follow the direction of the land. Between April and October, (when the easterly monsoon is blowing to the northward,) they are generally to the southward of west, or between that point and south-west ; but during the westerly monsoon between west and north-west.
Upon getting to the westward of the north-west Cape, the wind becomes more southerly, and draws to the eastward of south, as the distance from the land increases, and will be found varying between S.S.E. and E.S.E.,-generally speaking, as far south as the parallel of 30° of sonth latitude; after which, it is mostly to the westward of south, so that ships making a passage to the southward, along the west coast of New Holland, will rarely be able to make any easting, before reaching that latitude, particularly during the summer months. In the winter, a ship may occasionally make a quick passage to the southward, if happening to be upon the coast during a northerly gale, and as all these gales are preceded by north-east winds, a sufficient offing may be gained, to enable her to run on, when the winds get to the southward of west.
ON THE MOST SEASONABLE TIME for Felling TIMBER.
(From the Philosophical Transactions.) The custom of felling timber in the south of England differs from that of Staffordshire, only in two things, viz.-In the time of felling, and manner of barking. It being felled here in the spring, as soon as the sap is found to be fully up, by the trees putting out, and then barked after the trees are prostrate, the sap yet remaining in their bodies; whereas there it is first barked, (in the spring as here) but before it is felled, the trees yet living and standing all the summer, and not felled till the following winter, when the sap is fully in repose.
Now in the spring season, and some time after all the trees are pregnant and spend themselves, as animals do in their respective offsprings, in the production of leaves and fruit, and so become weaker than at other times of the year; their cavities and pores being then turgid with juice, or sap, which the trees being felled at that time still remain in the pores, having no way of being otherwise spent, and then they putrify, not only leaving the tree full of these cavities, which render the timber ENLARGED SERIES. NO. 12.--VOL. FOR 1841.
weak, but breeding a worm, as testified by both Pliny and Mr. Evelyn, which will so exceedingly injure it as to become altogether unfit for great stress. Now all timber felled at this time of year, whether the juices putrify, or otherwise evaporate, or dry away, is not only subject to rift and gape, but to shrink so considerably, that a piece of such timber of a foot sqnare, will usually shrink of an inch; than which says Vegetius, nothing is more pernicious if used for the building of ships. To which Julius Cæsar adds, that though ships may be made of such moist timber, felled in the spring, yet they will certainly be slugs, not near so good sailers as ships made of timber felled later in the year.
In all which circumstances most of the ancients so very nearly agree, that none of them advise the felling of timber for any sort of use before autumn at soonest; others not till the trees have borne their fruit, which says Theophrastus, must always be proportionably later, as their fruits are ripe later in the year: others not till mid-winter : not November says Palladius: nay, not till the winter solstice, says Cato ; and then too in the decrease or wane of the moon, between the 15th and 23rd day of her age, says Vegetius; or rather according to Collumella, between the 20th and the new moon. In general says Theophrastus, the pak must be felled very late in the winter, not till December, as the emperor Constantinus Pogonatus positively asserts, the moon too being then under the earth, as it is for the most part in the daytime in the first part of its decrease. And the felling of oak within those limits, they call tempestativa cæsura, felling timber in season, which they all unanimously pronounce, if thus felled, it will neither shrink, warp, uor cleave, nor decay in many years; it being tough as horn, and the whole tree in a manner, as Theophrastus asserts, as hard and firm as the heart, with whom also agrees Mr. Evelyn. If you fell not oak, he says, till the sap is in the rest, as it is commonly about November and December, after the frost has well nigh nipped them, the very saplings thus cut will continue without decay, as long as the heart of the tree.
And the reason of this is briefly given by Vitruvius, because the winter air closes the pores, and so consequently consolidates the trees; by which means the oak, as he and Pliny both express it, will acquire a sort of eternity in its duration; and more so if it be barked in the spring, and left standing all the sammer, exposed to the sun and wind, as is usual in Staffordshire and the adjacent counties; by which they find, by long experience, the trunks of the trees so dried and hardened, that the sappy part in a manner, becomes as firm and durable as the heart itself.
And though this way of barking and felling of timber were unknown to the ancients, as perhaps it is to all the world except those few connties, yet they seem not anacquainted with the reason of the practice; for Seneca observes, that the timber most exposed to the cold winds, is most strong and solid, and that therefore Chiron made Acbilles' spear of a mountain tree, Homer also tells ns that the spear of Agamempon was made of a tree so exposed; for which Didymus gives for reason, that being continnally weather beaten, it becomes barder and tongber. And Pliny says expressly as much for the sun, as they for the wind, viz :-That the wood of trees exposed to the sunshine is the most firm and durable ; for which reasou also it is, that Vitruvius prefers the limber on the south of the Appenine, (where it winds about and encloses Tuscany and Campania, and strongly reflects the constant heats of the sun upon it, as it were from a concave,) incomparably before that which grows on the north side of the same hill in the shady moist grounds; and his reason is, that the sun not only exhales the superfinous moisture of the earth, whence the trees are supplied in such shady places with too great a quantity, but in great measure the remaining juices oul of the trees themselves, rendering the timber of them the more close, substantial, and durable; which certainly it would do much more effectually, if the bark were taken off in the spring of the year, as in Staffordshire where the people use this method for their timber, though but for private uses. And inuch more should it be done for so public a concern as the building of ships, where tough and solid timber is much more necessary than in ordinary. There is indeed an act of Parliament, 1 Jac. I, chap 22, which forbids felling timber for ordinary uses, in consideration of the tan; at any other time than between the Ist of April and last of June, when the sap is up and the bark will run. To which I readily answer, that perhaps the legislators did not consider that the bark might be taken off in the spring, and that the tree would live and flourish till the ensuing winter; so that though the tree be not felled till the winter solstice or January following, yet the lanner is not at all defeated of his tan, but has it in due season. And in that very act of parliament there was an exception of the timber to be used in ship building, which might be felled in winter, or any other time; as I am told all the ancient timber remaining in the Royal Sovereign was, it being still so hard that it is no easy matter to drive a nail into it.
It is true indeed that the barking or peeling the tree standing, is somewhat more troublesome, and therefore rather more chargeable, than when they are prostrate; and that it is likely people have therefore usually felled their timber as well for shipping as other uses, in the spring of the year, for the sake of the more easy and cheap barking it, rather than any thing else. It is also true, that timber is harder lo fell in winter, it being then so compaet and firm that the axe will not make so great an impression as in the spring; which will a little increase the price of the felling and its sawing afterwards; but how inconsiderable these things are in comparison of the great advantage of this manner of felling is self-evident.
The greatest objection that can be urged against this practice, is, that if the timber be not felled till mid-winter or January, where it grows in coppices and woods, they cannot perhaps enclose their young sprigs so soon as some may imagine needful, and therefore they may be backward to fell their timber at that season. To which I answer, that the timber so felled in woods or coppices may be easily carried off, before the second spring, and so the prejudice be small; but what will quite remove this inconsiderable difficulty, is, that perhaps it may be expedient, that no timber whatever, growing in woods or coppices be at all bought for the King's yards, because that timber growing in such shady places, and so fenced from sun and wind, as timber in woods for the most part is, cannot be so good as that which comes from an exposed situation, such as it usually has in forests, parks, and hedge-rows, or open fields; where at least it is indifferent, if not belter for the pro
prieter, that it be felled in winter, when the grass and corn is off the grounds, than in the spring itself. And the officers designed for that purpose may buy all their timber under the conditions of its being felled in winter, after the bark has been taken off in the spring in due time.
Extract of a letter from Mr. Anthony Van Leuwenhoeek to the Royal Society, concerning the difference of timber growing in different countries, and felled at different seasons of the year.
“ As to the difference of timber felled in winter from that felled in summer, the common opinion is, that the former is stronger and more lasting, as being more close and firm ; but his own opinion is, tbat there is no difference, except in the bark and outermost ring of the wood, which in the summer are softer, and so more easily pierced with the worm. Wood consisting of hollow pipes, which both in summer and winter are full of moisture, they do not shrink in the winter, and therefore the wood cannot be closer at one time than another, for otherwise it would be full of cracks and clefts. The sudden and unexpected rotting of some timber, he conceives to proceed from some inward decay in the tree, before it was felled ; having observed all trees begin to decay at first in the middle or heart of the tree, though possibly the tree may stand and grow for near 100 years afterwards and increase in size all along."
He says he was once of opinion that trees growing in good ground, but increasing slowly, were the best and strongest timber; and that those trees which in few years grow large were the softest and brittlest, the contrary to which, on enquiry of experienced workmen he found to be true, and instances in elm of 80 years growth, which was eleven feet in circumference, and proved excellent tough timber.
The age of trees is to be known by the number of rings to be seen when the tree is cut across, in each of which is one circle of large open pipes, now the fewer there are of these large pipes, the stronger the timber is; hence those trees that make the largest growth in a year must be the closest and strongest; and therefore those trees that grow in warm countries grow fastest, and are the best and toughest timber, which he confirms by Riga and Dantzic oak, which is of slow growth and proves spongy and brittle timber; whereas the contrary is observable in English and French oak, which grows faster, and is excellent limber.
The WeatieR.-1. Its Changes ; 2. The design of the Circular Hur
ricane ; 3. The Variable Winds of the North Atlantic.-Considered
by Stormy Jack. Tue general natural system of the variations of weather throughout the world, appears so complicated, that, considering the lapse of ages which have succeeded the first essays to explain the seeming mystery, it is not a matter of wonder that the idea of its being beyond the intelligence of man to fully comprehend, should have been entertained. The apparent contrarieties, anomalies, aud observed capriciousness with which its workings are controlled, seem to defy the utmost ingenuity of the most indefatigable meteorologist to account for satisfactorily. What faith
then is to be placed in the predictions of a Moore, a Murphy, or any other divining almanac computor?
The changes often follow in such rapid succession as to be truly astonishing; yet how few in the busy round of human occupations, duties, pastimes, and pleasures, allow but an instant of thought on the causes of such phenomena? But “thinking men” or such as are imbued with a spirit of observation, know that as a whole ; that is to say, in the aggregate results, the system of nature is, and cannot be admitted to be otherwise than perfect. In the details, in the periodic returns, indeed, we are apt to imagine that we detect irregularities; and hence the source of the perplexities which assail those who deal only with the abstract question: to our wonder, however the philosopher, the man of enlarged views, who surveys the whole panoramic scheme, dealing first with particulars, next, amplifying into generalization, and finally calculating the amount of evidence deducible from facts, informs us that a balance is always struck with precision, in a lunation, a season, or a year. And it has been thought that a recurrence of similar weather takes place at long intervals, such as in the period of nineteen years, or what is scientifically termed a lunar cycle; or, in twenty-eight years, which is the solar cycle.
Our theories appear to be more or less faulty even in the present state. Nothing else, indeed, could be expected. The period required to draw just conclusions, and the close and incessant habit of observation necessary for obtaining data for that purpose, are so urgent, that even though an individual could be found possessing perseverance and determination enough to afford his undivided attention to the object; his entire life would be considered too short, to bring the whole matter into a state approaching toward perfection. But by a wise distribution of labour, which might be greatly lessened by a universal association of enlightened and scientific societies of Europe and America, and their Colonial associates in other parts of the world, so that the duties of ob. servation and registering may devolve on many, instead of being dependant on one or two only, there is scarcely a question that meteorological science, which has been so long neglected, would very soon begin to ascend toward that station to which it is deservedly entitled.
It may be observed, however, that upon the whole, we possess a tolerable clear and satisfactory outline of that portion of the general system which embraces the action and apparent causes of most of the particular winds:-1. Those which are so far steady throughout the year, as to be deemed perennial. 2. Others so nearly regular in their change as to be termed alternating. 3. Those whose recurrence are looked for with a degree of certainty, and are called periodic. 4. Land and sea breezes which are designated reciprocat. 5. Circular storms, or hurricanes.
With respect to the uncertain winds, or those which have obtained the name of general or variable, as much could not have been said or advanced hitherto, and indeed scarcely yet, as the inquiry has only began but a very short time.
The old phantasie of these winds being occasioned by the reaction of the atmosphere from the rotation of the earth, will, probably, give place