dead level, the power of one horse is sufficient to draw with ease, and at a good pace, a load of from twelve to fourteen tons, when divided amongst several carriages linked together.

The foundations of the rails are fixed in a much more solid manner than usual; and, as the horses do not draw between the rails, but on the outsides of them, and upon separate paths, so their trampling cannot injure the foundations of them, nor can they throw, as usual, any sand or mire upon the rails, which, of course, will never be obstructed thereby.

The peculiar construction of the carriages allows them not only to turn without the least difficulty in any deviating direction, and upon a curved rail-way of the shortest radius used, for instance, of twenty feet; but also to leave the rails, and be conveyed over common roads, like any ordinary waggon. These carriages can go on therefore without any interruption, through towns and villages, and over bridges, where the rails cannot be continued; and they also remaining loaded, till they arrive at their final destination.

By a very simple and easy contrivance, my carriages can also be turned from off the rails at any point where it may be found necessary, as either to avoid other waggons meeting on the same track, or to pass by those which they have overtaken, and return again into their first line; so that no siding places, turning plates, nor any other apparatus of these kinds, are necessary for such an operation; and which can be performed almost as quickly and easily as upon a common turnpike-road.

This very important improvement affords the advantage that a double track of rails will be sufficient for the most frequented traffic or intercourse; and for which, in the common way, five or six parallel tracks would have been requisite; and also, that any number of slow moving and heavy waggons can pass on the same line, and at the same time, with as many light and quickly moving carriages, and whether moving in the same or in opposite directions.

To employ the power of steam or other first moving powers, with the greatest advantage, and with the least possible expense, in the propelling of all sorts of carriages upon rail-ways; I have discovered a new principle, by which the power and motion of stationary steam-engines, and other machines, established at considerable distances apart, along the rail-roads, and working without interruption, can be imparted to any number of loaded carriages passing upon the rail-way, from one steam-engine or machine to another, without the employment of drag-ropes or chains, or indeed of any intermediate apparatus, and yet with any reasonable degree of velocity!

A rail-road and carriages, constructed upon this new plan, and with all these improvements and new inventions (the reality of which is partly proved by experiments made upon a tolerably large scale, and is partly founded upon the most infallible principles, and for the success of which I will make myself responsible), cannot fail to have a decided superiority over canals, as well as over rail-ways of the present construction commonly used in Great Britain.

This superiority has already been acknowledged by a committee of the Royal Academy of Sciences, and by committees of the Agricultural and Polytechnical Societies at Munich; and who, after having examined my plan, and assisted at the experiments, have made and published very favourable reports thereon. And although there is in this country a party strongly interested in canals, yet all our proprietors and capitalists, and also the majorities of both houses of our representative assemblies, are so well instructed and disposed, that my plan for uniting the two greatest navigable rivers in Germany, the Danube and the Rhine (through the Mayn), by means of an iron rail-way of my invention, is about to be adopted.

But I am convinced, that no where in the world, the introduction of this new plan of rail-ways would afford such immense advantages as in the United States, where the most rapid and prodigious progress in every branch of in

ternal improvement, industry, and commerce, protected by the wisdom of an enlightened and liberal government, and supported by the public spirit of an enterprising nation, are already the admiration of all Europe; and where, to arrive at the highest degree of national wealth and prosperity, nothing more is wanting, and nothing can be more desirable, than the greatest possible multiplication and facilitation of internal communication.

By adopting this plan, instead of the ordinary English system, the iron rail-way between the Baltimore and the Ohio, the construction of which is already decided upon, might be established with much greater advantage, and with a saving of nearly two millions of dollars.

It has lately been proposed to unite the Chesapeake bay with the Ohio, by a canal between Georgetown and Pittsburgh; and the expense of this canal is previously estimated at 22,575,426 dollars, of which sum nearly one-half will be required for the middle section alone, on account of the great number of locks, and a most expensive tunnel, by which this part of the canal is to be conducted over the highest point of the Backbone mountain. As far as I am able to judge, from the report transmitted by a messag● from the President of the United States, and published at Washington last year, it appears to me that a double track of iron rail-ways, with a sufficient number of stationary steam-engines, executed in the most complete and solid manner, would answer the purpose infinitely better, and save about two-thirds of the above sum, and as much of the time required for the conveyance of all articles, from one point to the other. Light vehicles, with passengers aud mails, might be transported upon this rail-way with the greatest safety and convenience in thirty-six hours, by day and night. Besides there would also be the very important advantage, that the rail-way might be used during the whole year, with very few interruptions; whereas, the navigation upon canals, in that climate, is generally confined to eight months only. If, however, my plan could

On the Circulation of the Sap in the Chara Translucens. 37

be adopted for the middle section only, and upon a length of seventy-two miles, a saving of from seven to eight millions of dollars might be easily made, and the traffic be carried on with greater expedition. But as, in this case, the loading and unloading from the vessels in the canal, to the carriages upon the rail-way, and vice-versa, would be rather troublesome, and attended with extraordinary delays and expenses; so I should recommend the construction of a rail-way for the whole line between Georgetown and Pittsburg, by which about fifteen millions of dollars would be saved, the whole work be finished in a shorter time, the expense of maintaining in repair be greatly diminished, the transport rendered more expeditious and convenient, and the annual income to the share holders and proprietors might be doubled, even with a lowering of the tolls.

The Chevalier JOSEPH DE BAADER, Knight of the Order of Merit of the Bavarian Crown; Counsellor of Mines; and Professor of Practical Mechanics, at the University of Munich; Member of the Royal Bavarian Academy of Sciences, and of the several Learned Societies; and one of the Directors of the Board of Agriculture, and of the Polytechnical Society at Munich.

VII.-On viewing the Circulation of the Sap in the Chara Translucens.

THE Editor has at length been gratified with a view of this interesting sight, and, indeed, in an unexpected manner.

Mr. Gray, of the British Museum, favoured him with a fresh specimen of the chara translucens about a month since, but which, being of a deep green colour, it rendered it impossible to see any thing passing in its interior. However, upon the Editor placing a joint of it, surrounded with water, and prepared in the manner described in our last volume, page 263, under his Varley's microscope, with a lens of the tenth of an inch focus; he found, that after remaining in water for several weeks, it had become nearly transparent, and he saw, for the first time, the sap flowing within it. On this, he changed the lens for one of the

38 On the Circulation of the Sap in the Chara Translucens. twentieth of an inch focus, and then had the pleasure of seeing it still more distinctly, flowing in two opposite directions, and exactly as described to him by Mr. William Tulley.

He afterwards prepared others, by scraping off the thin outward skin with a sharp knife, and thus rendered them transparent, in a manner indicated to him by Mr. Gray (and who, as well as other gentlemen in the British Museum, had witnessed the circulation of the sap in parts of the chara thus prepared six years since), and then found he could discern the flow of the sap as before, in the parts thus rendered transparent.

It is a curious fact, that a plant should thus retain the power of circulating its sap under water, for nearly a month after it had been removed from the place of its growth; and still more, that short portions of it, separated from the rest of the plant, should likewise possess a similar power; and this at a time of the year when vegetation is nearly at a stand. In short, this is the most interesting appearance which the microscope has ever afforded him.

Great care should be taken in scraping off the external bark, not to injure the sap-vessels, which have a delicately ribbed or granulated appearance; and the light of a candle or lamp is necessary to exhibit the minute globules of sap, slowly meandering along the ribbed channels in the vessels; sometimes, however, the globules of sap are larger than ordinary, and are, of course, more readily seen; but it requires an excellent microscope to view them distinctly, and a nice adjustment of the lens, as well as a proper management of the light; and, indeed, when Professor Amici, of Modena, first announced his discovery of this interesting fact, namely, the circulation of the sap in a plant rendered visible; it was considered as being owing to the very superior excellence of his reflecting microscope. The Editor, however, now finds, that his Varley's single microscope is fully capable of exhibiting this beautiful appearance.

It is not necessary that the watch-glass, in which the