The inconvenience arising from a diversity in the breadth of space between the two lines of rails, on one railway compared with that on another, became the subject of much discussion, and of animadversion upon Mr. Brunei's adoption of the "broad" gauge of 7 feet, on the Great Western line, in preference to the previous generally adopted "narrow" gauge of 4 feet 8 1/2 inches, between the rails. The inconvenience is especially felt in the transfer of many kinds of goods, where the "breaks" of gauge occur, as it necessitates the unloading the waggons on one line, and reloading other waggons on the other line; and as they are of very different dimensions, and require a different plan of loading, injury often results by the shifting and unpacking of the goods; besides incurring much labour, expense, loss of time, and not unfrequently pilfering. A great variety of mechanical contrivances have been, for years past, suggested to remedy the inconvenience of the change of gauge, but none that can be regarded as equalling the advantages gained by an uninterrupted or uniform gauge.

To determine what ought to be done under these difficulties, a government commission has been appointed to inquire "whether in future acts of parliament for the construction of railways, provision ought to be made for securing a uniform gauge, and whether it would be expedient and practicable to take measures to bring the railways already constructed, or in progress of construction, in Great Britain, into uniformity of gauge, and to inquire whether any other mode could be adopted of obviating or mitigating the evils apprehended as likely to arise from the break that will occur in railway communication, from the want of an uniform gauge." The commission was dated 11 July, 1845, and consisted of the following members: Sir J. M. Frederick Smith, Lieutenant-Colonel Royal Engineers, Professor Airy, Astronomer Royal, and Professor Barlow; names in which the public deservedly place the highest confidence for their intellectual capabilities and perfect integrity.

These gentlemen called before them such persons as they deemed most competent by their situation, knowledge, or experience, to afford them correct information on the subject of their inquiry, and had produced before them such books and documents from the various railway companies as appeared to be the best calculated to aid their researches. They personally examined into the usual course of proceeding on various railways, both at home and abroad, especially those which are incident to a break of gauge. Having inspected several locomotive engines, as well as various mechanical contrivances, invented either for the general use of railways, or for obviating the special difficulties presumed to arise from the break of gauge, and having carried their investigation to the utmost useful limits, they drew up a Report, which we shall now proceed to give the substance of, in a condensed form; as all the material facts bearing upon the subject seem to have been investigated with scientific intelligence, and correct judgment, and entirely free from party bias to any of the great rival companies, whose interests are affected by the decision of the question propounded; moreover, because many of their deductions from the evidence elicited, form useful data for the guidance of railway engineers.

The attention of the commissioners was first directed to ascertain whether the break of gauge could be justly considered so great an inconvenience as to require the interference of the legislature. This important part of the inquiry is treated under the following heads; viz. first, as applying to fast or express trains; secondly, as applying to ordinary or mixed trains; thirdly, to goods trains; and fourthly, to the conveyance of troops.

1. As applying to Fast or Express Trains; the commissioners observe, " We believe that the inconvenience produced by a break of gauge will, in some respects, be less felt in these than in other trains, because the passengers travelling by fast trains are usually of a class who readily submit to many inconveniences for the sake of increased speed on the journey; the inconveniences of a break of gauge are reduced, in this instance, to the removal of the passengers and a moderate quantity of luggage."

2. As applying to ordinary or mixed Trains. - "In these trains the passengers considerably exceed in number those who travel by the fast trains, and they have generally a much greater quantity of luggage. To such travellers a change of carriage is really a serious inconvenience, and it is a well-known fact that persons travelling by railways in communication with each other, but under different managements, endeavour to make such arrangements as to admit of their travelling by those trains which afford them the accommodation of occupying the same carriage from the beginning to the end of their journey.

"The managers and directors of railways are well aware of this feeling, and in some instances accommodate the public by enabling travellers to avoid a change of carriage on the journey.

"It is by the ordinary or mixed trains that private carriages and horses are conveyed, and the removal of either from one truck or horse-box to another, at any part of the journey, would be attended with inconvenience and delay; and with regard to the horses, it would involve considerable risk.

"We arrive, therefore, at the conclusion, that the break of gauge would inflict considerable inconvenience on travellers by the trains now under consideration.

"The change of carriages, horse-boxes, and trucks, and the transference of luggage of an entire train of much extent, must, even in the day-time, be an inconvenience of a very serious nature, but at night it would be an intolerable evil, and we think legislative interference is called for to remove or mitigate such an evil."

3. As Applying To Goods Trains

"From the statements made to us by carriers on railways, and from our own observation, we are induced to believe, that not only a considerable degree of care, judgment, and experience is necessary in the stowage of merchandise in railway waggons, but also, that it is desirable that when properly packed the articles should, generally speaking, not be disturbed until the journey is completed. We find that in the arrangement of merchandise, the heavier goods are placed at the bottom, and the lighter at the top of the load, and so secured as to prevent friction as far as practicable from the jolting of the waggons; and it is considered very desirable with a view to prevent loss by pilfering, that the sheeting, which is placed over the load, should not be removed till the completion of the journey. Indeed, acting upon this principle, carriers find it profitable to send their waggons partially filled from various stations on the line, thereby increasing their toll to the railway company, rather than incur the risk of loss by theft, to which they would be exposed by uncovering the waggons on the journey, to fill up with intermediate local goods waggons that may have started with light loads from one of the termini.

"In the conveyance of machinery and articles of a similar class, which are both heavy and delicate, it is of the utmost consequence that the load should not be disturbed between the beginning and the end of the journey. The traffic upon the line of railway between Birmingham and Bristol has been greatly restricted by the interruption of gauge at Gloucester.

"In respect to the conveyance of minerals, the inconvenience of a break of gauge would be very serious; the expense of the transfer would be sensibly felt; moreover, many descriptions of coal are subject to great deterioration by breakage.

"In regard to various articles of agricultural produce, the loss by removal would be less than on other classes of goods; much inconvenience, however, would be found in the transfer of timber; and the difficulty of shifting cattle, would be so great as to present an insurmountable obstacle to such an arrangement from the excited state of the animals after travelling by railway, and the resistance they in consequence offer when it is attempted a second time to force them into a railway waggon."

4. As applying to the Conveyance of Troops. - "This is another use of railways which we have deemed it necessary to consider. Although a break of gauge on the line of route would produce both delay and confusion, yet, as it is usually practicable to give notice of the intended movements of a body of troops, the inconvenience of the break of gauge might be so reduced, as not to be an evil of great importance; but in the event of operations for defensive objects, against an enemy, the inconvenience would assume a serious character.

"It would appear, that, for the defence of the coast, the proper course would be to retain the great mass of troops in the interior of the country, to wait until the point selected by the enemy for his attack should be ascertained with certainty, and then to move upon that point such an overwhelming force as should be adequate to the emergency.

"The troops should be carried with their equipments complete in all their details, and with their artillery and ammunition; and it therefore appears indispensably necessary, in order to insure the requisite supply of carriages, where perhaps little or no notice can be previously given, that the whole should be conveyed in the same vehicles from the beginning to the end of the journey."

After considering the subject in several other points of view, which it wou'd be needless to specify, the commissioners came to the conclusion that a break of gauge would be a very serious evil.