This section is on too small a scale to shew either the height of the embankments or the depth of the cuttings: and though it has not suited my convenience to spare the time necessary for examining the section deposited in Parliament, yet as the cubic yards of cuttings and embankments amount to nearly twenty-three millions: as the map and section I have just mentioned shew ten tunnels (some of which are a mile and upwards in length): and inclined planes, in unbroken rises of 6, 8, 10, 11, 13, 20, and 25 miles, there can be no doubt but that much deep cutting and high embanking is included in it. Now though I do not mean to imply that the expense of all cutting and embanking could have been saved, by taking proper advantage of the power of ascending heights, which is imparted by the momenta of the velocities whereat locomotive engines now go, yet I do mean to state it as my full conviction, that had this railway been (as the second prospectus of the Liverpool and Manchester Railway, stated that line should be) “laid down and arranged with that skill and conformity with the rules of mechanical science, which will equally challenge approbation, whether considered as a national undertaking of great public utility, or as a magnificent specimen of art” the whole of the anticipated expenses of deep cutting and high embanking would have been expunged from the estimates; it being certain, that deep cuttings, high embankments, and long inclined planes are no more evidences of engineering skill, than winning a battle by hard fighting is of generalship: while the expense of the numerous “very small cuttings varying from 8 to 10 feet,” which are spoken of in the “Minutes of Evidence taken before the Lords’ Committees,” might as certainly have been saved, and those rises passed over by the vehicles in consequence of their momentum; as a cricket ball will roll over a mole-hill.

But if these remarks are applicable to the Birmingham Railway—the line of which, was I believe, laid out in 1831—what must be said relative to the now proposed London and Bristol Railway?

For nearly twelve months the principle of avoiding level, and constructing “undulating railways” has been discussed, in consequence of Mr. Badnall having taken out a patent for, and published a work, proposing such “undulating railways”: and though, owing to the fall on your line being wholly (as well as greatly) one way, it is not necessary to express any opinion here on a proposition, which appears to have for its object the construction of unlevel railways in preference to level ones, and the labour of toiling up hill for the sake of the momentum to be obtained by running down hill, yet as, in consequence of it, the effect of momentum in carrying moving bodies up ascents, has been largely and widely adverted to for the last twelve months (nearly), it must have been within the expectation of every one, that, let the gentleman who has been employed to lay out the line of the Bristol Railway be anxious as he might, to avoid any “undulating” proposition, he would be equally anxious to call in the aid of all known and established principles, to diminish the expense of the line he was required to lay down. [32]

Now, nothing, I believe, is more certain, than that if a vehicle be moving along a level at the rate of 2¾ (2.7272) miles an hour, it will, on coming to an inclined plane, and provided the operation of the power which overcame friction on the level, be continued, so as to neutralise and (as relates to counteractive effect) annihilate friction during the ascent, “swing” itself up, and rise to the height of (that is, its momentum will cause it to rise to the height of) three inches perpendicular; let the angle of ascent, or rate of rise of the plane, be what it may.

Equally certain is it, that if the velocity of the vehicle be twice 2¾ miles an hour, that is 5.4544 miles, the momentum will (under similar circumstances as to counteraction of friction) then cause the vehicle to rise up said inclined plane to four times the height to which the former velocity raised it; or to the height of one foot. And it is equally certain, that the momenta imparted by increased velocities will, under the circumstance of the friction of the vehicle being overcome, neutralised, and (as relates to counteractive effect) annihilated, by the continued operation of the moving power during the ascent, cause the vehicle to rise up any inclined plane to the perpendicular heights stated in the following table:—

Carriages moving on levels, at theunder-mentioned velocities, the motions of which are changed fromhorizontal to ascending, by means, either of circular or angularascents.

Have momenta, which (friction being counteracted andneutralised) will cause them to rise to the under-mentionedheights (perpendicular) above the level where those velocitieswere attained: let the rate of rise, or angle of ascent, be whatit may.

MILES.

MILES PER HOUR.

PERPENDICULAR.

2¾

or

2.7272

3 inches.

5½

or

5.4544

1.0 foot.

11

or

10.9088

4.0 feet.

22

or

21.8176

16.0 do.

44

or

43.6352

64.0 do.

88

or

87.2704

256.0 do.

176

or

174.5404

1024.0 do.

352 [33]

or

349.0808

4096.0 do.

Now, let it have been proper as it may, that the gentleman whose name appears as “Engineer” to the Bristol Railway, should (in laying out that line) have avoided encumbering the subject with the “undulating” question, there can be no doubt that it was incumbent on him to diminish expense in every way which established principles admitted. And as the usual railway rate is now 20 miles an hour, while that rate will give momentum enough to cause any vehicle to rise up any inclined plane to the height of 13⅓ feet (perpendicular) above the level on which it was running at the rate of 20 miles an hour, it is necessary only to lay out the line of this railway in levels, and rises of 10 feet each, to avoid (very nearly, if not quite) all necessity for cutting, or embanking; while deep cutting, high embanking, and tunnelling, might (except in very peculiar cases) have been as certainly avoided, as erecting a suspension bridge will obviate the necessity for piers and arches over a river. Yet does not this gentleman appear to have any more called in the aid of this law of motion, than did those equally “eminent engineers” who laid out the line of the Liverpool and Manchester Railway; or those who have laid out that of the Birmingham Railway: the “Report” of the public meeting held at Bristol, on the 30th July last, stating that “although the line of country (except for about 30 miles at the Bristol end) is very advantageous, yet the comparative levelness of the railway will be attained by a great deal of deep cutting, and several tunnels;” while the prospectus issued from the London office of the Company states, that “the construction of a road so nearly level, in the hilly country about Bath and Bristol, will, unavoidably, be a costly work.”

The length of the Birmingham Railway is 112½ miles; that of the Bristol Railway “from 115 to 118 or 120 miles,” average 117½. The estimated expense of the cuttings, embankments, and tunnels, of the Birmingham Railway is 429,286l. or 3,185l. per mile. The same expense on the Bristol Railway is (835,300l. + 15,000l.=) 850,300l. or 7,236l. per mile; that is, above twice as much: and this too, notwithstanding that the Report states that “this expensive part of the work, fortunately, lies principally in two of the most favourable materials—the chalk and the freestone;” and also notwithstanding that the estimate of the Birmingham Railway has undergone two years’ scrutiny, and the most rigid investigation, by several Parliamentary Committees; while that for the Bristol Railway is the result of only a “preliminary survey,” directed by a “Provisional Committee:” so that were it to be increased as the estimate for the Birmingham Railway has been increased, it would be many times as much as the similar work on that railway. Indeed, the parties themselves have made a considerable increase already: 10 per cent. being added to the above amount of 850,300 by the Bristol Committee, and 7 per cent. by the London Committee; [34a] so that 978,494l. is the whole amount at present allowed for works, which taking proper advantage of the momentum of the vehicles would have saved.

Yet, with well-known laws of motion thus set at nought and neglected, and with expense thus unnecessarily as well as most enormously added to, are the Committee—gentlemen who were, unavoidably, as entirely dependant on the opinion of their engineers, as the Ministry of 1789 were upon that of the “Insanity Doctors,” relative to the mental affliction of George III.; or as those of 1830 were on that of the physicians who attended George IV. during his long illness—under circumstances of such entire dependence on the opinion of their engineers, are the “Provisional Committee” of the Bristol Railway led into the following expressions of approbation in their Report: “The Committee think it but justice to say, that the zeal, the diligence, the ability and other valuable qualities manifested by these gentlemen, have given them ample reason to congratulate themselves on their choice”!; and “The Committee, in conclusion, repeat that they have carefully availed themselves of the resources of skill and experience in investigating the probable cost of the railway.” [34b]

Now as, were I to presume to manifest “skill, experience, ability, and other valuable qualities,” such as these, with respect to your line, or thus to throw away, not only hundreds of thousands, but also half millions, on any other, I should be sure to experience the truth of that proverb, which says that merely looking over the hedge shall subject one man to the operations of “the finisher of the law,” while another man may steal the horse with impunity, I must avail myself of this law of motion, which “skill, ability, experience, and other valuable qualities” so neglect and despise, to get loads up the rise which you wish to surmount, without resorting to deep cutting or high embanking.