avail themselves of it, and communicate the result to the public; it would gratify at least the writer of this article.

Ever Pointed Pencils.

WE should be at a loss to name an article which in so short a space of time had so completely won the favour of the public, and put out of use one which was possessed by almost every person, and worn in almost every pocket, as has the ever pointed pencil. What may next be done in this age of rapid improvement, we may probably learn tomorrow; we think, however, that it will not appertain to an instrument of this kind, excepting it may be in its embellishments, as in point of utility it seems well to deserve the motto of ne plus ultra.

It ought to be universally known that the inventor of this ingenious instrument, was not himself the patentee. We are indebted for it to Mr. John J. Hawkins, civil engineer, a citizen of the United States, although a native of England, and now a resident there. Mr. Hawkins lived for several years in Philadelphia, but returned to England some five and twenty years ago, with the intention, however, of soon returning to the United States, an intention which he has always cherished, and in writing to his friends here, he has uniformly expressed the hope of soon returning home.

Mr. Hawkins might readily supply a new version of "A Century of inventions" made by himself; many of them manifesting talents of a very high order, but in most instances not calculated to increase his fortune in this age of utility; and in those which might have done so, as in the case of the ever pointed pencil, which he sold to Mr. Mordan for a small sum, the fruits of his genius have been reaped by others.

66

At one period Mr. Hawkins was the proprietor of a very interesting museum in London, consisting almost entirely of his own mechanical contrivances. It served as a striking proof of the fertility and versatility of his genius, but as its merits could not be appreciated by the million," it brought him no other reward. We have now, among our papers, a catalogue of this exhibition, and may hereafter particularly notice some of its contents. The Physiognotrace, by which so many thousand profiles have been taken, first at Peale's museum in Philadelphia, and subsequently in numerous other places, was invented by him, as also was another ingenious instrument, the Manifold Letter Writer, operating likewise upon the principle of the pentagraph, by which two or three pens were made to act by the direction of one.

We have been led to the recording of the preceding remarks and memoranda, from having recently obtained a very beautifully finished ever pointed pencil from the manufactory of Mr. Wm. H. Hale, of Brooklyn, New York. Although the manufacture has become one of great extent in this country, it is but recently that the productions of our workshops have been able to vie with those of England in point of high finish and embellishment, but such is now the case, and the one to which we have just alluded, is the most elegant

and tasteful that we have seen. We had recently noticed in the shops some which were ornamented in the same style, but whether or not by the same hand, we cannot tell; if they were, they exhibit the imperfection usually attendant on earlier efforts, whilst that before us manifests the effect of accurately made machinery, directed by the hands of skill and taste. The ornamenting of the stem is of the kind very properly denominated damask; the pattern is produced by a ground formed by the ruling of fine lines upon a polished surface, leaving a brilliant wreath of flowers and foliage, which has the appearance of being raised above the ground. The point through which the lead passes, we observe, is of steel; an improvement that renders permanent the part which was most liable to fail. If we have any objection to this pencil it is its great beauty, which we are unwilling to mar by forcing it into the company of penknives and cents. EDITOR.

FRANKLIN INSTITUTE.

Continuation of the Report of the Committee of the Franklin Institute of Pennsylvania, appointed May, 1829, to ascertain, by experiment, the value of Water as a Moving Power.

(Continued from p. 157.)

WHEEL NO. II.

THE foregoing tables contain the results of the different experiments made with wheel No. I. These being finished, that wheel was removed and No. II. (fifteen feet in diameter,) substituted for it, upon the same axis. The breast was altered to adapt it to the curvature of the wheel, and the requisite change made in the tail

race.

The proportion of friction in wheel No. II. to the weight, was ascertained by the method already described as having been applied in the case of No. I. This gave one per cent. for the ratio in the wheel as well as in the drum above. The reduction in the ratio of friction having taken place in both the wheel and drum, seems to point to the increased smoothness of the gudgeons, and their supports, as the cause of the diminution.

We proceed to calculate the amount of friction for the different weights applied in the experiments. The plan pursued will be that adopted in determining the friction of wheel No. I.

First. Constant inactive weight borne by the gudgeons of the wheel and drum during the experiments.

Weight of the wheel,

Weight of that part of the chain which was

1900 lbs.

between the barrel of the shaft and the drum, Weight of the drum,

Total constant inactive weight,

2364 lbs.

23.64 lbs.

Friction upon this at one per cent,

Second. Constant weight resisting the mo

tion of the wheel, and which was borne by the gudgeons of the wheel and drum.

That part of the chain which was between the barrel of the shaft of the wheel and the ground,

The iron basket used to contain the weight,
Three bars of lead weighing together

Total constant resisting weight,

Friction due to this weight at one per cent.

Total friction from constant weight,

The centre of gravity of the water in the buckets of the wheel, when supplied by chute No. 3, (Fig. II. Plate V.) was 5.00 feet from the axis of the wheel, and the barrel about which the chain was wound was one foot from the same axis; hence, to raise 257 lbs. the constant resisting weight, and overcome a friction of 26.21 lbs. the constant fric

20 lbs.

126 99

111 99

257 lbs.

2.57 lbs.

26.21 lbs.

tion just found, required a weight of water of 56.64 lbs. Friction due to this at one per cent.

Whole amount of friction when 257 lbs. was raised,

To find the additional friction due to each of the bars of lead which were used as weights, we have,

Weight of the lead,

To balance this weight and the friction due to it, (103 lbs.+1.03 lb.) or 104.03 lbs., required, at 5 feet from the axis, a weight of water of

Total,

Friction for each bar of lead,

.57 lb.

26.78 lbs.

1.24 lb.

An examination of the amount of friction at the several chutes in wheel No. I. showed such slight variations for the friction due to each lead, that it was not considered necessary to apply calculation to each of the chutes by which water was admitted to wheel No. II., the friction was taken as just determined for all the experiments with. this wheel. The distances of the centre of gravity of the loaded part of the wheel when water was admitted through the different chutes, were for chute No. 1, 4.61 feet, for No. 2, 5.1, No. 3, 5.0, No. 4, 4.2.

When eight leads were added to the constant weight in the basket the end o (Plate III. vol. vii.) of the shaft was suspended. By a calculation exactly similar to that given in page 79, vol. viii. the friction for each lead, after the eighth, was found to be 2.95 lbs.