The present number concludes the fourth half-yearly volume, of the New Series of the American Railroad Journal, and likewise brings us to the termination of the eighth year of its existence. Having abstained from any thing of the kind during the progress of the last volume-we will venture at its close to take a review of our labors, and return thanks to those to whom it is due.

It will be found on examination, that the quantity of original matter is nearly one half of the volume, and much of this too, is from the pens of gentlemen well known in their profession, and fully able to contribute to the general stock of professional intelligence. We can safely say that no effort has been made to procure these contributions, other than by a simple request, and in many cases we have been largely indebted to voluntary contributors.

To the writer of the vigorous and well reasoned articles, signed "Ful ton," we are greatly under obligation for a series of papers, which have been extensively copied throughout the State, and which will be found to contain a more lucid statement of the resources, condition, and future prospects of the Erie Canal, in regard to its enlargemant-than we fear can be found in the documents of the canal board itself. We hope for a continuation of these papers, and among other topics we desire to have from Fulton," a criticism upon the famous Report on the future revenue of the Erie Canal, laid before the Legislature during the last session. The gentlemanly tone of "Fulton's" language has rendered these papers generally acceptable while the sound reasoning and well drawn conclusions have not failed to carry conviction to the minds of those who have given them ap attentive perusal.

We are also indebted to our esteemed friend William R. Casey, for a number of excellent communications. That on the Western Railroad, is peculiarly interesting as it developes the resources and prospects of a work

which, although not within our own territory, will have an important bearing upon several of our main lines of communication with the west. For this and his other papers, Mr. C. deserves our best thanks, and we hope for many more in our next volume.

From Mr. Charles Ellet, Jr., we have received several valuable reports, and a description of the Schuylkill Wire Suspension Bridge, the engraving of which as appended to No. 5, being a present from Mr. Ellet of no small value. When engineers not only furnish us with useful matter, but also provide the illustrations already engraved, we feel ourselves under heavy obligations, as the expense of this kind of work is entirely beyond our means. We hope, however, that Mr. E. will not consider that he is freed from further obligation to assist us.

We can hardly find a number of the Journal, either in the present or former volumes, in which we do not find ourselves under obligations to our indefatigable friend "J. E. B." We are particularly indebted to him, for several admirable summary, and comparative views of the various important lines of railroad in the United States and in England. The short and pithy notices of this gentleman, have done much to the diffusion of popular intelligence in regard to Railroads, and his articles always are accepted with a hearty welcome. We may remark that the aid we have received from this gentleman, is not to be measured by the number of artieles which bear his signature, for his ever ready eye detects whatever may prove serviceable, and been the means of providing us with many useful items.

Mr. Roebling, and Mr. Cushman, have likewise furnished us from time to time with articles of interest, and we are happy to be able to rank them among our regular contributers. The communications of Mr. Roebling have one unusual character, which has always rendered them doubly welcome-they are written in the plainest possible hand, and the extraordinary neatness of his diagrams and formula, have saved us much trouble, and himself much mortification in correcting errors. Some fatality however, appearsto have attached to the communications of Mr. Cushman, and to have rendered numerous errata necessary. We beg leave to apologise to Mr. C., promising to use every effort in our power to prevent a recurrence of such mistakes. The proof of the article in question was read several times, and by different persons, and yet a few errors crept through unobserved.

The valuable notice by Mr. John M. Fessenden, of his new rail and chair, accompanied by cuts, has been treated with apparent neglect, the cause of which was the illness of our engraver, and the impossibility of obtaining the cuts for an earlier number. We trust that Mr. F. will not be discouraged by this circumstance, from contributing his ever welcome

notices.

Mr. Shotwell, has likewise been so kind as to furnish us with a quantity of original matter.

Mr. Williams and several other gentlemen, are also entitled to our thanks, for various notices; a repetition of which is respectfully requested.

Mr. Aycrigg, who has furnished us with matter of interest, we hope will continue his valuable assistance. We understand that he has made the investigation of the Steam Engine a matter of much study, and we desire to hear from him upon this point.

In respect to an article entitled "English and American Railroads," we find that we were right in our conjecture, and that they were written by Mr. Klein, the companion of the Chevalier de Gerstner. We are in hopes that an arrangement will be made with this gentleman, to become a regular contributor to our Journal.

We have made it a point particularly to acknowledge our indebtedness to our friends, as it has been an unusual circumstance to receive so many original communications in so short a space of time; and we hope that this promising commencement will not disappoint us and our readers. Our chief aim being to render our Journal as useful as possible, we always wish to see in its pages a large portion of original matter from members of the profession-conceiving that by this means, we are not only contributing to the diffusion of really valuable matter, but also bring about a better acquaintance between Engineers themselves.

In conducting a public Journal of any kind, it appears impossible to avoid controversy, and in fact, we are not opposed to a fair and critical examination of various topics; the constant fear however, is, that these things may be carried to excess. We wish it to be distinctly understood, that we do not admit articles because we agree with the writers in any respect, and we therefore disclaim any idea of the adoption on our part, of the opinions of any or all of our contributors, unless so expressed. It is to be desired, that when gentlemen feel themselves called upon to dispute the opinions of others, it may be done in the manner least calculated to wound the feelings, and best adapted to bring about a fair understanding. We have had in the present volume, but three cases of controversy, two of which originated in matter previously published, and therefore may be considered as a discussion growing out of the subject. The third case, however, was originally commenced as a criticism, in our pages. We hope that this matter settled, that gentlemen who have taken part in it, may be induced to furnish us with something of another character.

We are well convinced that the value of the Journal will be greatly increased by the mutual exchange of opinion through its pages, and we repeat it, that the best results to the profession will grow out of the increasing contribution of Engineers, each one chosing that topic for the consideration of which, he has had the best opportunity.

We consider that one feature in the past volume is a good one-having curtailed our subscription list, by cutting off nearly all our non-paying subscribers, we have endeavored to avoid all dunning notices. We are fully persuaded that this curtailment has enabled us to do more justice to our real friends, and spared them the mortification of reading what was intended for others.

Several arrangements have been made, which will, we hope add to the value of the next volume of the Journal; and we shall spare no pains to make it worthy of the kindness which has hitherto been extended toward

us.

For the American Railroad Journal, and Mechanics' Magazine.

EARLE'S METHOD OF PRESERVING TIMBER.

MESSRS. EDITORS.-The above method of curing timber, in spite of the incredulity, and prejudice, and opposing interests of rival processes, begins, we understand, to be very highly accredited. The processes of Kyan and of Bill, (the latter improved by Mr. Renwick) have long been known, and their sufficiency for their purpose well established; and by the addition now, of this other process of Dr. Earle, we may congratulate the public on having an enlarged choice of the mode, in which every one may, according to his preference, avail himself of an important benefit. But it is of the lat ter alone, we at present, intend to speak.

The favorable attestations of the learned committee of the Franklin Institute, and of many of the most scientific men of the U. S., as published some time since by Dr. Earle, have not been without their effect on public opinion; and we learn, with increased satisfaction, that the value of his process, has recently been recognized by the honorable Secretary of War, and gentlemen presiding in the several bureaux of his Department. That, as a first step towards the adoption of it into public service, the preparation of a large quantity of timber is now in progress, under the superintendence of the patentee, at the Watervleit arsenal in this State, and that there is just reason to believe that similar patronage will presently be extended to it by our Naval Department also. We find too, in some of the Philadelphia newspapers, that the State Penitentiary, near to that city, requiring extensive renewal of the wooden parts of the cells and central building, is to be repaired, under a decision of the Inspectors, with timber cured by this method. These are very creditable proofs of the estimation in which this process is now held by many whose intelligence fits, and whose interest and duty prompt, them to examine and judge capably of it. Nor is it to be regarded as a less honorable testimony of its merit, that it is attracting foreign attention; and especially, that it is likely to be soon employed in the naval architecture of Russia.

But the signal advantages of this process are, that it employs materials of the greatest abundance and cheapness, and of a perfectly inoffensive character. By an improvement too, very recently adopted by Dr. Earle, in his mode of conducting the process, the cost of the apparatus is greatly reduced, and its construction so improved in simplicity, and the freeness of its parts, as to be easily transportable to, and employed in, any situation in which it can be required. It is capable of being accommodated to operations of any magnitude; from the smallest to the greatest; and the terms on which the right of using this process are granted by the patentee are, as our inquiries inform us, of the most liberal kind.

With such a mode of giving durability to the blocks, how desirable does it become that our city should enjoy the comforts and advantages of wooden pavements;-especially that our Halls of Justice and our Temples of worship, should be freed from the disturbing noise of passing vehicles, at those hours when peace and quietness are most desirable. We confess it has been one of our chief objects in attempting this favorable, but, we believe, just view of Dr. Earle's process, to bring it precisely before our city authorities, and induce them to move in a matter at once so practicable, so desirable, and withal so reasonable.

By giving currency to the above through one of the pages of your valuable Journal, you may, perhaps, do acceptable service to many; and will oblige one of your subscribers, and

A FRIEND TO IMPROVEMENT.

New York, June 5th, 1840.

To the Editors of the American Railroad Journal, and Mechanics' Magazine.

GENTLEMEN. I find by the editorial remarks in your last number, that my explanation of the comments upon Professor Renwick's account of American Steam vessels, and the accompanying table, have not proved satisfactory, as my last communication is preceeded and followed by remarks of your own, the authorship of which I do not question, in which some of your former objections are repeated and amplified. The table in my first letter appears now to be the principal part objected to, and this because the power of the engines is not properly estimated. The dimensions of the cylinders are given, however, and every engineer and editor is, or ought to be, able to elucidate the power of the engines, if they are properly proportioned in other parts, and they are permitted to assume any pressure, of steam they choose, as they certainly would be in this case. table was compiled with a view to show the actual consumption of fuel by the different engines named while working at the usual rates; but I shall be pleased to see it amended by yourselves or "an Engineer" and the power of all the engines calculated by the same rule, whatever that may be.

The

But for better understanding the subject let us examine it a little more in detail. The Rochester had one cylinder of 43 inches diameter, and 10 feet stroke; the Liverpool two cylinders of 75 inches diamater each, and stroke of 7 feet each. The Rochester was worked 26 strokes per minute, with steam at a pressure of from 20 to 40 lbs, per square inch, and the cylinder filled about of its length at each half stroke. To do this requires about 655 cubic feet of steam per minute.

The Liverpool was worked 16 strokes per minute, with steam at a pressure of 3 to 4 lbs per square inch, and each cylinder filled of its length at 2 each half stroke, which required about 10300 cubic feet of steam per minute. To produce this large bulk of steam at that low pressure, requires more than twice the amount of caloric that is required to produce 655 feet at even