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MR. BIRAM'S IMPROVEMENTS IN OSCILLATING ENGINES. (SECOND NOTICE.) Fig. 3.

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MR. BIRAM'S IMPROVEMENTS IN OSCILLATING ENGINES.

The accompanying figures show the system as applied according to the first arrangement, to the propelling of a railway locomotive carriage. Fig. 1 is a side elevation, partly in section, of the engines; fig. 2, an end elevation; and fig. 3, a plan. The engines are proposed to be placed fore and aft, and worked in connection by means of double cranks.

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cations. In one it is applied to the water supply pump of a locomotive engine, worked by an eccentric on the shaft of the driving-wheels. In another it is adapted to a fire-engine, whereby "the same work would be performed with one cylinder, which is now done by two of the same diameter, the friction would be reduced one-half, and a rotary mode of working be substituted for the reciprocating." Another arrangement for adoptFig. 2.

Mr. Biram illustrates the advantages of his system by several other exemplifi

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ing the system to a fire-engine is shown, in which an upright lever is introduced and the piston worked by a rowing action, which is allowed on all hands to be the best of any. Mr. Biram observes farther of this last arrangement, "It is also well-adapted for a ship's pumps, in which case the pipe above the valve-box should be conveyed through the ship's side, as near as conveniently may be above the load water line; it will be also evident that, by attaching a horizontal rod to the end of the upright lever, and passing handles

through it at convenient distances (say about a yard asunder), a great number of men might be conveniently employed at the same pump; and further, that by attaching an air vessel, it would at once become a powerful fire-engine, by which the water could be sent to any part of the vessel." Mr. Biram's last exemplification is an air-pump, "by turning the handle of which in one direction, it is a condensing pump; and by reversing the motion, it becomes an exhausting one." Mr. Biram's claim is-1st, to "the con

structing of oscillating engines, whether worked by steam, water, or any other fluid, with passages placed as before described for the entrance and exit of the steam, water, or other fluid, to and from the cylinders, and opened or closed, wholly or partially in manner before described, according as the progress of the cranks, and the state of the steam or the cylinders may require.” And, 2nd, “the application of the same peculiar system of action to water-pumps, air-pumps, fire-engines, and other machines and instruments employed in the raising or propelling of fluids as before respectively exemplified and described."

METHOD OF COMPUTING THE DIRECT DISTANCE BETWEEN ANY TWO PLACES ON THE SURFACE OF THE EARTH, THE CORRECT GEOGRAPHICAL POSITIONS, OR THE LATITUDES AND LONGITUDES OF THOSE PLACES BEING KNOWN. -APPLICABLE MORE PARTICULARLY TO THE RUN OF STEAM SHIPS.

In reading the published accounts of the performances of some of the ocean steamers of the larger class that go on lengthened voyages, the distances they are said to run between one observation and another, when compared with the times that are stated to be occupied in accomplishing those distances, are sometimes very astonishing and eminently calculated to excite our surprise; and when placed in juxta-position with the performances of the swiftest sailing vessels, we are apt to imagine that the officers on board have fallen into some error in registering their remarks. It ought however to be considered, that steamers possess an immeasurable advantage over sailing vessels in running a direct course, being comparatively but little influenced either by wind or tide; whereas, a sailing vessel when working up against a head wind, being obliged to traverse on oblique courses, has both the distance and the time of accomplishing it greatly lengthened. In fact, the method of conducting a steam ship from one place to another, under any circumstances, is altogether a different thing from that of conducting a vessel under sails; and in this particular case, as well as in many others when the elements happen to be adverse, the practice of navigation has undergone a very complete and remarkable change; so

much so indeed, that the difficult and intricate manœuvring of fifty years ago on a stormy and turbulent ocean is now in a great measure assimilated to the mimic operations of school-boys on the bosom of a placid lake or a gently flowing river.

The problem which enables us to test the correctness of steam-boat logs, in so far at least as the distances are concerned, is that which assigns the direct distance between any two places on the surface of the globe, when their true geographical positions, or their latitudes and longitudes, are known. There is nothing particular in the problem itself, either as regards the difficulty of its solution, or the interest that attaches to it, being in reality well known to all the readers of general geography; but from its peculiar applicability to the subject we are now considering, we have been induced to propose it in an insulated form, independent of all other problems of a kindred nature, thinking that by so doing it will be more likely to meet the eye and arrest the attention of our readers.

It is generally understood, that the nearest direct distance between any two places on the surface of the earth, is an arc of a great circle passing through those places, and such, that if its plane were produced, it would pass through the centre of the globe and cut it into two equal and similar parts. And in like manner, if the planes of the meridians passing through the poles and each of the two places were produced, they would respectively pass through the centre of the globe and divide it into two equal and similar parts. But supposing that each of the planes above mentioned should extend no further than to the centre, they would cut out a solid gore or portion of the sphere, separated into two triangular pyramids supplemental to each other, and whose bases are portions of the spheric surface. It is to these pyramids so constituted, that we must apply for the solution of the present problem. Since the latitudes and longitudes of the two places are given, the compliments of the latitudes and the sum or difference of the longitudes, according as the one is east and the other west, or both east, or both west; are also given, the former constituting two sides of a spherical triangle, and the latter the angle at the pole comprehended between those sides, or be

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