tity, more or less, according to the amount of the fixed salts present, of sulphuret of lime in solution. This substance may be obtained from the first part of the operation when lime is used, or from the liquor of the wet purifiers of the gas-works. The sulphuret of lime decomposes the fixed salts of ammonia, liberating the latter substance in the state of hydrosulphuret, which may be treated in the same manner as that evolved in the first stage of the process.-[Sealed, Dec. 20, 1845.]

London Chemical Gazette.

On the Velocity of Atmospheric Jets.

COMMUNICATED BY Z. PARKER.

The following table of the velocity of atmospheric jets, under the given pressures, may be useful.

The table is constructed under the assumption that all fluids acquire equal velocities under the pressure of equal heights, without regard to their specific gravities; allowing the superincumbent column to be homogeneous with that portion at the jet. The formula is V = 64 h; and for a pressure of 15 lbs. per square inch, h=27,600 feet of homogeneous atmosphere. The height for other pressures in proportion.

In the Report of the Committee on Exhibitions, on page 368 of the December No., in lines 13 and 14 from foot of page, instead of WV. P. Cresson, read Walter Cresson.

JOURNAL

OF

THE FRANKLIN INSTITUTE

OF THE STATE OF PENNSYLVANIA,

FOR THE

PROMOTION OF THE MECHANIC ARTS.

FEBRUARY, 1848.

CIVIL ENGINEERING.

First Annual Report of the Directors of the Pennsylvania Railroad Company, to the Stockholders, October 30, 1847.

GENTLEMEN, The period has arrived when, under the provisions of the nineteenth section of the Charter of the Company, the Board are required to present to you an account of their proceedings before surrendering to you the trust which has been confided to them.

Upon entering the duties assigned to them, in the prosecution of a work of such magnitude, in which their fellow citizens hold a deep stake, and in which the future prosperity of the city is largely interested, the Board felt their responsibility, well knowing that a false step at the commencement would damp the ardor of its friends, and jeopardize its final success.

Earnest consideration was therefore given to the most effective organization of the Engineer corps, upon which success in a great measure depended, and the Board determined to place that department under an efficient head, who should control the whole, with two associates, to have charge, under his direction, of the two divisions of the road respectively.

In the selection of a Chief Engineer, the Board were fortunate in obtaining the services of Mr. John Edgar Thompson, a gentleman of enlarged professional experience and sound judgment, who had obVOL. XV, 3RD SERIES.-No. 2.-FEBRUARY, 1848.

7

tained a well earned reputation upon the Georgia road, and in whom the Board place great confidence.

The office of Associate, West, was filled by the election of Mr. Edward Miller, a gentleman well known and appreciated in this community, who has occupied several prominent positions in his profession, with entire credit to himself, and enjoys the merited confidence of all companies who have employed him.

As Associate, East, Mr. Wm. B. Foster, Jr., was appointed, a gentleman who has for years filled important stations, in connexion with the State works, and who has proved himself an able and efficient officer.

The experience of the past summer has satisfied the Board that in the organization of this department they have nothing to regret.

The Board, at an early day, turned their attention to an object, which they deemed it incumbent on them to secure if possible, for which their constituents had manifested great solicitude, and took immediate measures to prevent the Baltimore and Ohio Railroad Company availing itself of the Law passed by the Legislature of this State, granting to that Company the right of constructing a road from Cumberland to Pittsburgh.

To effect this, a subscription to the amount of three millions of dollars, and the payment of one million into the treasury of the Company, were required by the Act of Assembly, and to have fifteen miles of road put under contract for construction at each terminus of the Pennsylvania railroad, prior to the thirtieth day of July, 1847. The instalments were therefore called payable on the first days of May and July, and were promptly met by the stockholders. These instalments, with that already paid at the time of subscription, amounted to nine hundred thousand dollars, and the deficiency was met by payments, in anticipation of the fourth instalment, from Stockholders, who came promptly forward to a sufficient extent, some of whom paid up their stock in full.

In the month of July, contracts were made for the construction of the road the required distance, and on the second of August, the Governor issued his proclamation, declaring the law giving to the Baltimore and Ohio Railroad Company the right of way through Pennsylvania null and void.

The good effect of this measure upon the general interests of the Company has been made strikingly manifest, by putting it, in the offset, in a state of high credit, and by imparting to it a public confidence which cannot fail to facilitate future subscriptions that may be necessary for the completion of the road.

The policy to be pursued by the Board in the management of this work was plainly indicated.

The law requiring fifteen miles at each end to be put under contract was fulfilled, but at this point so unwise a course stopped.

With this exception, the attention of the Board was directed to the Eastern end, with a view of bringing into profitable use that portion of the road which would soonest make a return to the stockholders. An examination of the different routes which had been indicated by

former surveys and public opinion, led irresistibly to the conclusion. that the Valley of the Juniata was, on all accounts, to be preferred, presenting greater facilities, easier gradients, and less distance, with the decided advantage of being brought into profitable use at a much earlier period than either of the others.

Accordingly, it was determined to adopt and place it under contract as rapidly as it could be prepared by the Engineers. Twenty miles were let in July, which are now rapidly progressing towards completion. Forty miles further, to Lewistown, will be let to contractors on the twenty-sixth of November, and the Engineers are now actively engaged in locating the line, with a view of placing the remainder of the eastern division, to the base of the mountain, under contract early in the spring. As soon as the Engineers have completed their operations, a report from the Chief Engineer, with an estimate of the cost, will be made and published for the information of the stockholders. The surveys and location of the western division cannot be completed until early the ensuing summer, but sufficient information will be obtained from the surveys of this year to enable the Engineers to give an estimate of the cost of the whole road, with considerable accuracy. The line of the road upon the eastern side of the mountain has been finally determined and proves highly favorable. The whole length of the road from Harrisburg to Robinson's ridge, at the foot of the Allegheny, is one hundred and thirty-five miles, upon which there is no ascending gradient exceeding sixteen feet per mile to Lewistown, and twenty-one feet for the remainder of the distance, nor a descending gradient exceeding ten and a half feet per mile.

From Robinson's ridge, which divides the little Juniata from the Frankstown branch, north of Brush mountain, the ascent of the Allegheny is commenced, and overcome (with the use of locomotive power) by a gradient of about eighty feet per mile in thirteen miles, without encountering any extraordinary difficulties. This work will be left for a future period, and in the mean time a junction will be formed with the Allegheny portage by a branch line, six miles in length, from Robinson's ridge to Hollidaysburg, or some point further west. From the summit of the Allegheny to Pittsburgh, the line will pass over an uneven country, requiring maximum gradients of fifty feet per mile in both directions. The whole length of the road from Robinson's ridge to Pittsburgh will fall somewhere between one hundred and ten to one hundred and twenty miles.

The general plan determined upon by the Board is to proceed with the western section as soon as the eastern division is complete, unless means are provided to prosecute both simultaneously, and to bring them into use by connecting with the Allegheny Portage, while the mountain, or middle, division is in the course of construction.

From present prospects, the Board anticipate being enabled to run their cars from Harrisburg to Lewistown before the close of the winter of 1848-49, and the winter following, with the means now at their command, to connect with the Portage at Hollidaysburg, which, with the completion of the western fifteen miles, will give a continuous railroad communication between Philadelphia and Pittsburgh, with

the exception of fifty-five miles to be traveled by stages; and the Board anticipate at that time a very large proportion of western travel over the road.

The importance of securing a supply of iron in time early engaged the attention of the Board, and they were desirous of obtaining it from the mines of Pennsylvania. With this view, they offered to contract for a sufficient amount to afford an inducement to erect new iron works for its manufacture.

After some negotiations, they finally closed with the offer of David Reeves for fifteen thousand tons, the amount required for the eastern section, at sixty and one half dollars per ton, being about ten dollars per ton less than the market price at that time on the seaboard. The amount required, and prospect of future orders, determined the bid, which was considered a very advantageous operation for both parties. Mr. Reeves has commenced the erection of his works in Lancaster county, and will be prepared to deliver iron in the month of June next, being the time it will be required for the track.

Since the period when this enterprise was first undertaken, a marked change has manifested itself in the public mind with respect to its feasibility and prospects of profit. At that period, the subscription to the stock was considered by many as a patriotic endeavor to retain and extend a trade which legitimately belonged to this city, and which was about to be wrested from her grasp by her enterprising rivals.

A glance at the subscription book attests the existence of this feeling, for out of some twenty-six hundred subscriptions near eighteen hundred are for five shares and under. The books at that time were carried from house to house by the active friends of the road, who solicited even single shares, and the powerful aid of public opinion. was brought to bear upon the city authorities to induce a large subscription, lest private enterprise should be inadequate to the task. Of the importance of the work to the true interests of the city and State no one ever entertained a doubt. If any had been entertained, the recent disaster to the State public works of Pennsylvania must have removed it.

In a single night, the whole range of canal along the Juniata was swept by the flood; more than twenty thousand tons of goods in transit left along its banks, to be wagoned east and west at a heavy expense, and the channel of communication between the east and west interrupted for nearly two months, leaving the country full of produce, coal, and iron, unable to find an outlet to market for the next six months, and materially interrupting the business prospects of the merchants both of Philadelphia and Pittsburgh.

Such an occurrence, which the canal must at all times be subject to, has awakened the attention of the whole country to the necessity of pressing the work forward with the utmost vigor.

As an investment, this work is now viewed in a very different light from what it was a year ago.

Since the road has been seriously undertaken, with an earnest determination to bring it rapidly to a completion, its prospects have been more carefully scrutinized, and every fact which has been developed