The precise quantity calculated and provided must be made sufficient, or the consequences would be serious. The usual practice, therefore, of going ahead as fast as the engines will take the ship must be entirely abandoned. Careful observations, systematically pursued, will show the speed which, under different states of immersion, can be attained without a disproportionate expenditure of power, and to this speed the engines must be limited. A little experience will probably show that, under certain circumstances of immersion of the ship, or of the state of the sea, it may be economical to force the screw or the paddle engine, the one more than the other. This can only be determined by somewhat delicate and very precise and accurate observations. These must be made. It is not merely a question of degree, but our whole success depends upon the application, not of one, but of all these refinements.

A close study of the relative speed of the ship, as ascertained by the self-registering logs, and by continuous astronomical observations, compared with the expenditure of power in the engines as indicated by the number of revolutions constantly registered, and the power expended as measured and recorded by the chief engineer, will be necessary for some time to come, and until indeed the management of such large ships becomes as much a matter of rule as it is now, or perhaps ought to be more than it is, with smaller ones.

As to the use of the sails, while the engines are nevertheless in full action, it must be entirely a matter of experiment, and an experiment in which, again, all previous habits and prejudices must be set aside.

Whether a sail steadies such a ship usefully or not can be, and must therefore be, positively determined by measurement with proper instruments, and not by the sensations; and the result upon the speed of the vessel as compared with the power expended must, in like manner, be ascertained by positive observations and measurements. No past experience can do other than mislead. It is quite possible that the same means which improve the rate of the present large steamers may be prejudicial to our performance.

The commander must appreciate the necessity of all this study and attention to what is rather mechanical than nautical, or our voyage will be a failure. The difference between the peculiar qualities of such a floating mass as compared with those of the largest steamer now afloat, is likely to be as great as between the last and a 100-ton cutter; and the most prejudiced believer in the acquired skill of an old sailor who had learnt to manage the small vessel in the most perfect and masterly manner, would not expect him to be able to handle one of the present large steamers, still less to elicit the best performance out of her. In the same degree the man who takes the command of our ship must, if he is to succeed, enter upon his duties with a belief that he has nearly all to learn, at the same time that this feeling is perfectly consistent with a proper confidence in his own powers to master the new circumstances, and to succeed with this as he may have done with other vessels.

Finally, the commander’s attention must be devoted exclusively to the general management of the whole system under his control, and his attention must not be diverted by frivolous pursuits and unimportant occupations. I believe that even in the present large steamers much advantage would result from relieving the captain from all care of the passengers and cargo; but in our case, where we may have to provide for thousands instead of hundreds, and arranged in different classes, and living in completely separate saloons and compartments, the present system of a captain dining at the table and associating with the passengers would be impracticable, even if it were desirable. But for much more important reasons, and on general grounds, I think that while the commander is of course supreme over every department, he should not be embarrassed by undertaking any one, still less should he have his mind occupied with the troublesome and frivolous concerns of a vast hotel, nor should he be hampered by the necessity of attending to the hours and the forms of a large society. Moreover, I consider it essential that he should by his presence and control keep up the position and the sense of responsibility of the chief officers under him, by living and messing with them; the commander and those acting immediately under him must occupy a more dignified position than they now do.

The result of all these general views is, that the command of this ship must be considered to consist mainly in the superintending and keeping up in a high state of order the perfect working of a highly methodical pre-arranged system, by means of which the ship is to be made to go like a piece of very accurate machinery, precisely in the course which has been pre-arranged, and precisely at the speed, and with the consumption of power, which has been ascertained to be the highest attainable with the requisite economy; and there must be a proper establishment of assistants, competent to control each department of this system. As regards the constitution of this establishment, I consider the commander should have a staff of chief officers or captains. I believe three will be necessary, with a fourth performing general duties and ready to take the place of any one of the three; that one of them should always be in command of the ship (under the commander); that, besides these chief officers, there should be a master, corresponding to a master in a Queen’s ship, who would have assistants and calculators or clerks, whose duties would be to keep the ship’s reckoning, to keep up perfect and continuous observations, to calculate with precision and set from hour to hour the exact course by compass which has to be followed, to keep in the course determined upon by the captain, to keep a series of accurate observations and records of all matters that can affect the ship’s movements—duties involving an amount of science and practical astronomical and mathematical knowledge which requires a superior education, and which is found only in this class of men. The duty of the master would be therefore to supply the science necessary for the conduct of the ship, and to be the commander’s cyclopædia and book of reference, to be able at any moment to report to the commander the exact position of the ship and her course, and the variation of her compasses, and take the soundings, if any, to note the fact of a change in the temperature of the water, indicating approach of ice, and any other symptom or fact which can affect the ship’s movements—all which should be determined by continuous observations methodically and mechanically made, and not be dependent upon the chance of the commander’s anxiety or greater or less forethought. The chief engineer should also be a superior man, selected more for his general qualifications as a good director of men and machinery, than as a mere marine engineer. These should form a staff, and be of a standing to live and mess with the commander; so that each department should thus be furnished with a chief competent for the special duties of his department, and reporting to and acting under the general control of the commander.

That the principles thus laid down as to following exactly a prescribed and predetermined course, and as to regulating exactly the consumption of power and consequently of fuel, and the keeping up a system of what may be termed scientific observation for the purpose of ensuring this regularity, I submit should be rigidly enforced; and the commander should be required to adopt these principles as the guide of his conduct, and to use the measures that are placed at his disposal for working this machine in the manner and with the precision pointed out.

Letter on the Duties of the Chief Engineer.

March 19, 1857.