before,

216

Mr.Rennie on the Friction

by a lever, and the time noted by chronometers.
of brass ground to each of the plates. The valve was opened

the other stopped by a valve, the
recorded as
inserted into a block of hard wood fastened to the cistern, and
diminishing their sections; and one extremity of the tube being
mities were carefully enlarged, to prevent any wire edges from
drils, were as accurate as possible; their diameters at the extre-
The diameters of the tubes, from having been drawn on man-

experiments

were

t=

Circular Orifice made in a brass plate 1 inch diameter, inch thick.

Constant height of
the surface of the
water above the
centre of the orifice.]

Real time in dis-
charging one cubic
foot.

Theoretical time in discharging one cubic foot.

Ratio of the theo

retical to the real
discharges.

Vena contracta

Circular Orifice in a brass plate 2 inch diameter, th inch thick.

Circular Orifice in a brass plate inch diameter, th inch thick.

Circular Orifice in a brass plate 4 inch diameter, th inch thick.

381

N.B. Each result shows the mean of four experiments.

Remarks.

The phenomena relative to the form and direction of veins of spouting fluids, and the remarkable inversion of the fluid veins at certain distances from their orifices, have been so fully noticed in Experiences sur la Forme et sur la Direction des Veins et des Courans d'Eau; par George Bidone; Turin, 1829," that it is unnecessary to state further than that they have been completely corroborated in the foregoing experiments.

(To be continued.)

Novel Inventions.

Fumigating Apparatus.

A philosophical instrument maker in Bristol, named Braham, has lately constructed a simple apparatus, to be employed for the purpose of fumigating hospitals, ships, and the apartments of sick people, and other places impregnated with foul and deleterious vapours; and for rendering the atmosphere in such places pure and fit for healthy respiration: a subject which cannot be too strongly recommended to the attention of the public in these days of alarm and apprehension, as the most effectual means of preventing the spread of those internal disorders that are now so prevalent under the general title of Cholera, and which in all probability arise from the impure state of the atmosphere in certain localities, more than from any contagious influence.

The apparatus is intended to be carried about the apartment in the hand. It consists of a cylindrical box of tin, about the size of a dark lanthern with a handle behind to carry it by, and an opening in front, through which a small spirit-lamp is to be introduced into the

VOL. VIII. SECOND SERIES.

2 F

box and reservoir resting on the bottom. In the opening or mouth of the box at top, a small flask or glass retort is placed, containing a small quantity of chemical mixture, which by the heat of the lamp below is made to distil, and consequently to throw off a vapour, the properties of which are calculated to decompose any putrid matter that may be floating in the atmosphere, and also to supply oxygen, which is the great supporter of life.

This apparatus is so compact and simple in its construction, that it may be taken from place to place in the pocket may be introduced into the most confined recesses of an apartment with perfect ease-is in operation in less than a minute after lighting the lamp-gives out in a very short time sufficient gas to purify any moderately sized room, and in cost does not exceed two or three shillings.

Metallic Hone.

A metallic cylinder for sharpening razors, surgical instruments, and pen-knives, invented it is said by T. A. Knight, Esq. President of the Horticultural Society, has lately been manufactured by Mr. Huntly, of Regent's Circus, and is highly spoken of as perfectly effective and much more convenient than an oil stone, answering all the purposes of a hone, and rendering a strop unnecessary. This instrument is a cylindrical rod of steel, about a quarter of an inch thick, and five inches long. It is rendered perfectly smooth in the first instance, while in its soft state, and is the worked into extremely fine longitudinal lines, by means of fine emery or glass paper, previous to the steel being hardened. It has a silver or plated knob at the top end, by which it is to be held when in use, and when out of use, it is slipped into a cylindrical sheath, as a guard to its surface.

In using this instrument for sharpening the finer kinds of cutlery, such as razors, its surface is to be first moist

ened with a small quantity of sweet oil and a little rotten stone, or rouge, or indeed any kind of extremely fine grit is to be powdered upon it. The razor being then held perfectly flat upon the surface of the cylinder, is to be worked about in the same way as on a hone; and if the edge of the razor has not been previously rounded by careless setting, the fine lines and the powder upon the steel will very soon bring it to a beautiful smooth cutting edge.

The simplicity and convenience of this instrument is a great recommendation to it, and the cost it appears is as low as from two shillings and sixpence upwards.

APPENDIX

To the Report of the Select Committee of the House of Commons, on Patents.

Papers delivered in by John Farey, Esq.

[British Law of Patents for Inventions.]

(Continued from page 167.)

J. Williams against J. T. B. Williams, his Wife and another, in Chancery. An application to dissolve an Injunction previously issued by the Vice-Chancellor, to restrain the Defendants from divulging the secret composition of certain Medicines for curing Diseases in the Eye, and from preparing or vending those medicines. Heard 6th August 1817. Injunction dissolved.

The plaintiff had stated that he was the sole owner of the recipes of the medicine, which he had made and sold for many years; that he communicated the secret to his son, the defendant, and had put him in possession of his shop, and stock of medicines, with the intention of taking him into partnership when of age, under certain conditions; but those conditions not being fulfilled, and the

son threatening to expose the secret, the father applied to the court, and obtained the injunction to restrain defendants from proceeding. The son denied that it was any secret to him, when the communication was made by his father, for that he had been instructed in it in early life, by his mother, who had derived the secret from another, and had communicated it to her husband, the plaintiff.

Lord Chancellor Eldon. the injunction, so far as to restrain the son from selling the articles put into his possession by his father, in the confidence of a treaty for his becoming a partner when of age; for if that did not take place, he was bound to return the articles. But so far as the injunction goes to restrain the son from communicating the secret, upon general principles, I do not think the court ought to struggle to protect this sort of secret in medicine. The court is bound to protect patentees, but that is because they have published their But whether in the exercise of its jurisdiction, to decree the specific performance of agreements, the court ought to restrain a party from divulging a secret discovery, that he has promised to keep, is a question that would require very great consideration. In this case it is denied that there is any secret, and there appears no ground to support the injunction."

"The court was regular in granting

secrets.

Canham against Jones, in Chancery. An application to the Vice Chancellor to restrain Defendant from making and selling a Medicine called Velno's Vegetable Syrup, of which Plaintiff claimed to be the sole Proprietor. Heard before Sir Thomas Plumer, who refused the application, on the ground that the Plaintiff had no exclusive property in the Medicine.

Isaac Swainson had purchased the secret or recipe for preparing the medicine for £.600, thirty years before his death, and he continued all that time the sole proprietor and maker; by his will he Sequeathed it to plaintiff, who continued to make and sell the same preparation. Defendant had lately began to sell a medicine, under the same name.

Sir Thomas Plumer, Vice Chancellor. It is an erroneous notion, that there is an exclusive property now subsisting in this medicine, or that Swainson having purchased the secret, and disposed of it by will, had a power to give the plaintiff an exclusive right of sale. If such a claim of monopoly could be obtained without any limitation of time, it would be a much better right than that of a patentee. Nor do the acts of the defendant fall within the cases in which the court has restrained a fraudulent attempt by one man to invade another's property, by representing himself and his trade or productions, to be that other person's, in order to appropriate the benefit of a valuable interest in the nature of good will, consisting in the character of the trade or productions established by the individual merit of another.