promotion of scientific discoveries consists in the inadequate protection afforded by the law of patents, which gives to the discoverer the monopoly of the whole of his invention, yet allows others to steal any of its parts, and thus by uniting those parts so stolen with other inventions, or with stolen portions of other patents, to mock the law and laugh at the claims of other original

inventors.

That your Right Honourable House has recognised and protected literary property, by the law of copyright, in a much more efficient manner, and providing not only against the piracy of the whole, but also against the abstraction of any of its parts.

Your petitioner, therefore, humbly prays that your Right Honourable House will take into consideration the present inadequate protection to scientific discoveries, plans, models, and labours; and by extending the law of copyrights to the law of patents, or by awarding compensation and remuneration to the original inventors of all engines, plans, models, &c., when they are successfully appropriated by other persons to the same or other purposes, afford that encouragement to science and invention which the great railroads and other works now contemplated (from the success of your petitioner's project, the Liverpool and Manchester Railroad), imperatively call for.

And your petitioner will ever pray,

WM. JAMES.

ON CUTTING OFF STEAM AT PARTS OF A
STROKE.

BY JOHN MOORE, Esq.

To the Editor of the Railway Magazine.
SIR,

I BEG to submit the result of an investigation of the theoretical effect produced by cutting off the steam at part of the stroke of the piston, when compared with the steam continued during its whole stroke having an uniform density.

Fig. 1, 2, 3, 4, are to represent steam piston cylinders; the numbers within the cylinders, the density of the steam; and the divisions, the respective quarters of the cylinders.

The numbers on the right hand are the time elapsed in the steam's progression from to its adjoining.

In Fig. 1 the steam flows uninterruptedly from the boiler during the whole stroke of the piston, with the density of 14lb. per square inch, giving a power equal to 14lb. through the length of the cylinder in the time 56.

In Fig. 2 the steam is continued during one of its stroke at 14lb. density, it is then cut off, and acts expansively; in the next it is expanded into double space, and therefore at half its previous density, or 71b.; in the next expanded more, and its density 4.67; next expanded 4 more, and its density 3.50; the sum of these 29-17, as the cylinder is divided into 4, so divide 29·17, and we have 7·24 as the average performance of Fig. 2. Compare 7 with density of the steam 14, as 7 is of 14, time of steam in passing 7lb. through the 1st quarter, will be the number equal to half the steam's density, or 7; in the next 1, 14; next, 18.66; and in its last 1, 23:32; together, 62.98; one of the sum of the density of the steam is about 74lb.;

therefore 29-17 steam can take 74lb. through the length of the cylinder in the time 62.98.

In Fig. 3 the density of the steam is 28, the cylinder then contains the quantity of steam of Fig. 1 in of its space, and when expanded into its space will have the density of 14; when occupying another of the cylinder, its density will be 966; and when the cylinder is filled by its steam its density will be 7.25; its sum, 58.91, divided by 4, gives an average of 14-72lb. in the time 62-98, for its passage through the length of the cylinder.

In Fig. 4, the steam contained in of this cylinder is equal to the contents of Fig. 1, and, therefore, has a density of 56 when it has expanded into double its space, occupying the cylinder; its elasticity or density will be reduced half, equal to 28lb.; upon its expanding more its density will be 18-67, and when occupying the whole of the cylinder have a similar density as Fig. 1, using no more steam, but the cylinder of steam in Fig. 1 is equal only to 56 in the time 56, averaging 14. But in Fig. 4, the cylinder of steam in Fig. 1 produces an effect equal to 116-671b. in the time 63, averaging 29-17, being a double weight lifted by it in a little longer time, or as 63 is to 56, or it would take 14lb., the average of the work of Fig. 1, through a similar distance to the time 31.57; but in Fig. 1 the same weight and like quantity of steam required the time 56.

In conclusion, I may observe that the beneficial effects of cutting off steam, before it has forced the piston to the bottom of the cylinder, seems to be derived from the power at the commencement being in considerable excess to the work done, or the spaces gone through, therefore the sooner you cut off the steam the greater density it must be, and proportionably stronger must be your boiler. I am, Sir, yours respectfully, JOHN MOORE.

Bristol, September 12, 1830.

ON ENGLISH INVESTMENTS AND METRO

POLITAN RAILWAYS.

By B. J., Esq.

THE mania for indiscriminate speculations has, we imagine, somewhat abated its fury, and the extraordinary and extensive losses in the Spanish funds will cool the ardour of at

least the more sober among that class of persons who are fond of speculation. To me it has always been a matter of astonishment, that persons with their senses about them should enter into such risks in foreign securities at all, at least into such as by internal or external disturbances must be reduced in value to most ruinous loss, but more particularly in such unsettled countries as Spain and Portugal. I should hope that, with such ample plans for the employment of their capital in the various projects and improvements of our own country, we have people that will seek this more legitimate and useful means of investment, when they are not only sure of a higher rate of interest, but are, at the same time, aiding to give employment to every branch of manufacture, to agriculture, and commerce; assisting in the diffusion of knowledge, and fostering the genius of the country, rather than helping to bolster up the credit of other nations, which will never look to their own internal resources so long as another Rothschild can lead, and Englishmen follow, in taking any loans they require, which will inevitably end in never being paid. In looking to the various means for the employment of capital in this country, it would be impossible to enter into any numeration of them, I can only refer to your "Railway Magazine," and, believing in very truth we take the lead in all the useful mechanical works of the country, the highest proof of the civilization and prosperity of a country is in its roads. The social communication of men, as well as their commercial existence, depends upon good and expeditious means of transit, and as the best yet discovered unquestionably is that by railways, they therefore take the lead of all the works of national usefulness, and I confess I am therefore a warm advocate of them generally. I by no means recommend capitalists, whether large or small, to embark their money indiscriminately in their formation; some must be good, some bad, many better than others. Fortunate or judicious will be those who have entered into the good; for if the profit be unshackled, as it should be, they must unquestionably pay a high rate of profit.

It is not my province to distinguish among the various lines formed, forming, or to be formed; but I do believe if the lines are judiciously chosen, and well laid out, almost every one will pay a large per centage, where the distance is sufficiently long to make a charge, and not so long as to make the expences run away with the income, which must be the case in long distances, where there are no interme

diate stages, to make each section of the whole pay itself. The South-Eastern, for instance, depends almost exclusively on its termini, and, unless it goes to Brighton, never, I think, can pay.

The Eastern Counties' runs through a number of towns connected together, and, if there is any traffic between them, ought therefore to be profitable. The Blackwall Railway is too short to reduce expenses, or to make a saving in time. It will, therefore, save nothing in the run, nor will it give increased facilities, and, consequently, cannot increase the traffic, being dependent on that now existing to the Docks. It appears, indeed, to be too short for so great an expense in construction. The City and Richmond Railway, now in projection, would appear to meet our views in having a sufficient extent to embrace a large mass of inhabitants, always on the move backwards and forwards to some of the various points in its passage; and, as it will become the terminus in London of the different large railways in construction on the west and probably on the south, which do not themselves come beyond the outskirts of the City, it must pay, in my opinion, a very large profit, and be highly useful to the outskirts of the metropolis. The extraordinary increase in the numbers of omnibuses and other vehicles, as also that of their speed, as well as that of steam-vessels to all parts, all of which fill, is abundant proof of the public demand for increased facilities of transit, with as little trouble and as much comfort as possible. Upon that ground I point to the City and Richmond and Thames' Haven Railways as sure to pay a large profit to their subscribers, the first proposing to become the terminus to eight of the most important railways. One great feature of the former appears to be the relieving of the present crowded state of the Metropolis, including Southwark and Lambeth, from the omnibus system, which it will much help to do, and of the latter the convenience of its dock and landing-place.

I am, Sir, your obedient servant,

B. J.

GRAND MATHEMATICO RAILWAY DISCOVERY.

To the Editor of the Railway Magazine. SIR, Ir is rumoured that a splendid discovery has lately been made in the mixed mathematical sciences, of high importance to Railway Companies having tunnels and bad