This deplorable accident has given rise to much discussion on the subject of steam navigation.
The following letter in the Montreal Herald is interesting: -
To the Editor of the Montreal Herald:
Sir - I am extremely glad to see that the late melancholy event connected with the Shamrock is not to pass over with that calm indifference which many were led to believe from the report of the Coroner's inquest. There must have been some cause for the boiler's explosion; of that there can be no doubt, although neither captain nor engineer can account for it. The captain in his evidence, declares that his power extended to the regulation of the quantity of steam, or rather the amount of pressure upon the safety valve. I would ask, in the name of the public, in the name of those who have suffered, if he, the commander of the Shamrock, was a competent judge of the strength of a boiler to bear a given pressure of 70 to 80 lbs. per square inch; in fact was he a regular bred engineer and properly qualified to enter into all the details of a high pressure marine engine? If he was, then he might have the power of regulating the pressure of steam but if he was not, then he was decidedly taking more responsibility upon himself than any commander in her Majesty's steam frigate service.
The engineer declares, in his evidence, that he tried the guage cocks fifteen minutes before the time of the accident, and found water in all of them. I would ask him if he shut off the steam before trying the guage cocks? If he did not, then he nor no other person would swear there was sufficient water in the boiler, owing to the violent ebullition the boiler might be forming, and thus make all the cocks show water, although very different. Was there a glass guage upon the front of the boiler? If there was not, then no boiler, either high or low pressure, should leave an engineer's yard without one.
But the great question which the public wants solved, is the cause of the explosion.
1st. - the boiler might have exploded from not being manufactured sufficiently strong to resist the pressure it was intended to bear.
2nd. - It might have exploded from the water getting too low, consequently the tubes or plates getting red hot, thus causing the generation of hydrogen gas, which is as explosive as gunpowder.
3rd. - It might have exploded from having a defective safety valve. Each high pressure boiler ought to have two, one that the engineer might use at pleasure, and another self acting, over which he ought to have no control, and loaded only to the extent of within 20 to 30 lbs. per square inch of what the boiler is calculated to resist. These valves ought to be made as large as to allow the steam to get off freely as fast as it is generated - for I have known instances of boilers exploding just from the safety valves being too small, although every thing was correct every other way. Now, since I have no doubt the boiler of the Shamrock is properly examined by competent persons, some of the above causes will be found to have been the operating one.
Some person has declared, through the medium of the public press, that the safety of a low pressure boiler, compared to that of a high pressure is as 4 1/2 to 1. I can assure this gentleman and the public, that there is no more likelihood of an explosion taking place in a high-pressure boiler than there is in a low one, if each is manufactured with that degree of care and scientific skill which is actually necessary to insure safety to the public. To prove the truth of this, we have only to look at the number of high pressure engines used on railways, for be it known that there are no low pressure locomotives.
Amongst all the accidents that do occur upon railways, we never hear of boilers exploding, and I am certain this is principally to be attributed to the care of companies not employing any man to drive an engine but who is a through engineer. A part of the Polytechnic Institute of London is set aside for the particular purpose of educating those individuals who have a desire to take the management of an engine; he gets a diploma, after he has shown that he is competent, after that, people have confidence in giving him employment.
To conclude, I conceive there can be no public confidence in steam boat companies till some person, properly qualified, is appointed to examine and report upon all engines and boilers that ply from this city, at least every three months, and also examine all persons that are put in charge of engines or boats, to see if they are properly qualified to undertake the duties of that most responsible situation.
An Old Country Engineer
Montreal, 16th July, 1842