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February, during which period there were some strong gales from tr westward, between north-west and south-west, accompanied by heav rain, thunder, and lightning; but although there was a good deal < dirty weather, it was by no means constant, as there were occasions intervals of fine weather, with moderate westerly winds. This was th only bad weather on this part of the coast during the season, that coul be said to be caused by the westerly monsoon, (if we except the E.S-E squalls that do not occur in the easterly monsoon.)
While this weather lasted the easterly squalls were quite suspended, and the heavy bank of clouds that had generally been noticed in the south-east, had dispersed for the time, but after the strong westerly breezes had ceased, the weather was generally fine, and the wind mostly from some western point; there were occasional showers, and the clouds in the eastern horizon resumed their threatening appearance, bringing some hard squalls and rain from that quarter. In the middle of March, (being the time when equinoctial gales are looked for in most parts of the world,) there were two or three days of squally unsettled weather, with rain, that seemed to terminate the season of the westerly monsoon. After the first of April, the weather was invariably fine, and the easterly squalls had ceased to trouble us;—land and sea breezes became Tegular, and the easterly monsoon had no doubt set in to the northward, the strongest breezes now were from south-east, but generally speaking, the winds were light near the land.
It does not appear that the westerly monsoon blows with any degree of regularity to the southward of the 13th degree of south latitude, although for some degrees south of that, the weather is influenced by it, and winds between W.N.W. and south-west will be experienced; and from the appearances on many parts of the coast, there are no doubt strong gales at times, from the westward, that send in a heavy sea.
During the easterly monsoon, the weather is fine on the north-west coast, particularly in the months of May, June, July, and August. This is, undoubtedly, the best time for visiting it,—land and sea breezes are regular, and the temperature is very agreeable.
The average range of the thermometer on that part of the coast, between the north-west Cape and the meridian of 120° east longitude, during the above-mentioned period was between 75° in the middle of the day, and 60° at night, (on board the ship,) and the general course of the wind as follows, viz.
About sunrise, or sometimes a little before that, a breeze,springs up between south and S.S.E., and draws to the eastward as the sun rises, rapidly increasing in strength, and between ei^ht and eleven A.m., often blows a fiery breeze; towards noon it moderates, and rarely lasts until 2 P.m., after which there is a light breeze from north-east, which at times reaches to the north; the nights are mostly calm, or a light breeze from the south-westward. At the full and change of the moon, we found the'south-easlerly winds stronger than at other times; dews at times very copious.
All this part of the coast is subject to the effects of mirage, by which its outline is at times very much distorted, but generally speaking, it ceases with the strength of the breeze, and as the sun attains a little altitude. When the effect of mirage was observed in the morning, I 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 K.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 I I6lh 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 south 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.
The custom of felling timber in the south of England diners 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. 5 K
weak, but breeding a worm, as testified by both Pliny and Mr. Evelyn, which will so exceedingly injure it as to become altogether unnt lor 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 eape, but to shrink so considerably, that a piece of such timber of a foot sqnare, will usually shrink J of an inch; than which says Veeetius, nothing is more pernicious if used for the building of ships To which Julius C:esar adds, that though ships may be made of sucft moist timber, felled in the spring, yet they will eertainly be slugs, not near so good sailers as ships made of timber felled later in the year.
In all which circumstances most of the ancieuts 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, wbiett says Theophrastus, must always be proportionally later, as their truits 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 SS3rd day of her age, says Vegetius; or rather according to Collumella, between the 20th and the new moon. In general says Theophrastus, lb* oak must be felled very late in the winter, not till December, as tbe emperor Constantinus Pogonatus positively asserts, the moon too being then under the earth, as it is for the most part in the daytime in tbe first part of its decrease. And the felling of oak within those limits, they call tempestativa csesura, felling timber in season, which they au 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 whick 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 summer, exposed to tbe 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 barkkig and felling of timber were unknown to the ancients, as perhaps it is to all the world except those few counties, yet they seem not unacquainted 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 Achilles' spear of a mountain tree. Homer also tells ns that the spear of Agamemnon was mads of a tree so exposed; for whirh Didymus gives for reasea, thai being continually weather beaten, it becomes harder and tougher. 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 reason also it is, that Vitruvius prefers the timber on the south of the Appenine, (where it winds about and enclose* Tuscany and Campania, am] 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 sua not only exhales the superfluous 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 out 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 much 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 rises, in consideration of the tan; at any other time than between the 1st 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 tanner 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 limber 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 harking or peeling the tree standing, is somewhat more troublesome, and therefore rather more ehargeable, 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 to fell in winter, it being then so compact 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 eoppices 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 better for the proprieter, that it 1* felled in winter, when the grass and com is off the grounds, than in the spring itself. And the officers designed for that purpose may buy all their timber under the condiiions 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 Leuwenhoeekto 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, that 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 sixe 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 limber.
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 limber is; hence those trees that make the largest growth in a year most 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 timber.
The Weather.—1. Its Changes; 2. The design of the Circular Hurricane; 3. The Variable Winds of the North Atlantic—Considered hy Storing Jack.
The general natural system of the variations of weather throughout ibe 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, and observed capiiciousuess with which ill workings are controlled, seem to defy the utmost ingenuity of the most indefatigable meteorologist to account for satisfactorily. What fculh