monthly with those of other observers: and I obtained in return, sufficient materials for deciding in the affirmative the first part of the question above-mentioned, as well as for throwing, possibly, some light on the second; which, however, is one of too great difficulty to be treated with much success, except by combined and extensive observations.

Having adopted, at the commencement, a period beginning at the new moon, the first three years will be found thus arranged. From the close of the year 1809, however, I preferred the last quarter; as by setting out from this, the phases of new and full moon appear in the midst of their respective moieties of the observations.

One other circumstance I may here notice. I have prefixed to the calendar names of the months their numerical designations, and where I write myself, I use these in preference. This is the phraseology of the Society of Friends to which I belong, and is from principle, as well as education, a part of my form of Christianity. The reader who may not approve of this peculiarity, will therefore be pleased to tolerate it: which he will do the more willingly, on finding that it interferes but little with his convenience in reference.

The following is the method I use in noting my observations. About nine in the morning, I make the round of the instruments (the situation of each of these will be noticed, in treating of it in its place); I find it the securest way to do this with the slate and pencil in hand. The direction of the wind, for the past twenty-four hours, usually from memory, but with due reference to the present posture of the vane, is noted for the first column.

The actual place of the quicksilver in the barometer, with the place it has moved from, as indicated by the hand index, are put down for the second and third columns; and for the fourth and fifth the situation of the

two indexes of the thermometer, which are then adjusted with the magnet. The amount of rain is ascertained and noted for the seventh column. The actual place of the index of De Luc's hygrometer occupies the sixth column-but always a day in advance of the other observations: all of which, as relating to the past twentyfour hours, come under the date of the day preceding that on which they are thus noted. In other words, the day I use extends from nine in the morning to nine the next morning. The daily evaporation occupied the sixth column before I began to make use of the hygrometer. After inserting these in their places in a book, previously ruled, and the ruled page dated throughout, I add on the opposite page miscellaneous notes, from memory as to past, and from observation as to present phenomena.

Of the Wind and Vane.

In noting the winds, I have used only eight points of the compass: the observations are therefore in general but approximations to truth. I have endeavoured to give the prevailing wind for the day; neglecting this consideration at times, to show the order of succession, or an account of a remarkable degree of force.

If we reflect on the height of even the denser part of the atmosphere, and the great proportion of night to day in our winter months, when the winds are busiest, we shall be forced to admit that our knowledge of the currents in the variable climate of these islands is very imperfect. Like fishes inhabiting the bottom of an ocean, we are insensible to much of what passes over our heads.

The vane, however, is not the limit of our means. We know that certain winds always set in above, before they are felt below; and it is when they come so low, that we

can detect their direction (in the day-time at least) that they have the most influence on the character of the season. These subsiding currents may often be traced by bringing some elevated streak or spot of cloud, which may appear at first motionless, into visual conjunction for a short time with a fixed object, such as a tree-top, or the parapet of a house. Balloons are more effectual, as they show every current they pass through: but they are too troublesome for frequent use. The low currents, which glide up and down the valleys in a calm evening, are often amusingly marked out by the smoke; which they will carry to a small distance, and then return it at an acute angle in the opposite direction. And this means of detecting light winds is at no time to be neglected.

For the strength or violence of the wind, I have employed only the terms in general acceptation. An arbitrary estimate of the force by marks or numbers, I consider as conveying nothing more definite than the usual phrases; and I have never possessed an instrument for measuring the degree of force that satisfied me in use. Nor would the daily use of an instrument, if constructed on more certain principles, be convenient; except in prosecuting specially an inquiry into this subject. Perhaps some ingenious artist may one day overcome the difficulty for us, by making an anemometer, which shall register its own indications for the 24 hours. There is a good design for one, to show the wind and its force at the time of inspection, by Kirwan, which may be seen in the Philosophical Magazine, vol. xxxiv. p. 247, et seq. It is extracted from the Transactions of the Royal Irish Academy for 1808, and exhibits a good basis for the above-mentioned project.

I have always employed a very moveable and sufficiently elevated vane. As this instrument is often clumsily made and fixed, I shall take this opportunity to lay

down some principles, by attending to which, a workman may be enabled to set up a good one.

1. As to form: it should be simple, to ensure durability; and such as that the resisting surface may be as nearly as possible confined to one side of the spindle. It is curious to observe this principle so commonly violated on our public edifices. Either some inelegant caprice takes possession of the architect or artificer, or it is taken for granted that a new vane must be unlike any old one in existence. The shortest way to convince the workman on this point will be, to propose to him to solve the probable effect of making a vane alike on both sides: as he

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will soon see that such a vane would be continually taken on its broadside by the wind: consequently, that every approach towards this equality of resistance must both diminish steadiness, and increase the strain on the spindle.

2. As to suspension: a spindle of hard iron, tapering to a point not smaller than a writing crayon, should enter into a tube stopped by a harder substance. A flint, having a smooth concave face on one side, will answer for this, and it may be fixed in a socket as much larger than the tube itself as is necessary, and so joined to the tube. The spindle is likewise to pass through guides inserted in the tube, and to be sufficiently long, to allow for the subsidence by wear at top. On it, the moving part should rest in equilibrium: the counterpoise is best made by a loaded ball, carried out to the proper distance (which may be found by trial before fixing it) on a slender, single or double branch of iron. The whole is to be kept down on the spindle by means of a second, and larger, moderately loaded ball, mounted on the centre of the vane, and turning with it.

There are vanes to be had ready made in London, which fulfil pretty nearly these conditions, that of great durability excepted. This is best insured, where expense is not an object, by using copper well gilt for the material.

3. As to position: it is obvious that this instrument ought to be clear of deflections and eddies, from objects on the same or a higher level.* That it may the more easily be so placed, the spindle may end in a taper shaft,

*The site of Geneva remarkably exemplifies the effect of local position in this respect. Here, owing to the direction of the valley, the vanes point almost constantly either to SW or NE; the cross winds going over above their level.