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most frightful explosion which had ever signalized the Western waters. The question rose instinctively to our lips, Was it the Moselle? It was but too true. The rashness of the captain had most fearfully recoiled upon his own head, hurling with him to destruction more than a hecatomb of innocent victims, and this too the result of an effort to pass the very boat which had outstripped him on his previous trip.

This disastrous explosion, the most terrific, we believe, recorded in the history of steam, awakened for a time the public from their apathy. In Cincinnati, the scene of the disaster, a public meeting of the citizens was called, where, among other resolutions having for their object principally the relief of the surviving sufferers, one was passed, raising a committee of five, to inquire into the causes of this calamity, and “ to report such preventive measures may be best calculated hereafter to guard against like occurrences.” Upon Dr. Locke, one of this committee, devolved the principal labor of preparing their report ; and on the 15th of August it was submitted by the mayor to the city council, under the expectation that they would cause it to be printed. Several weeks, however, having elapsed, and no steps having been taken by that body towards giving it publicity, the committee asked and obtained leave to withdraw it, and it was afterwards procured of Dr. Locke by a number of the citizens, and by them given to the world. This report, which thus struggled into light, was limited in its range, by the terms of the resolution under which it was prepared, to an investigation into matters connected with that class of accidents arising from explosions. Upon this point, much valuable information was collected, and many useful hints were suggested. The result of the Doctor's investigations, brings him, we think, very justly to the conclusion, that the explosion on board of the Moselle, which utterly demolished the boat and destroyed the lives of one hundred and fifty people (p. 22), took place while there was a sufficient supply of water in her boilers, and was the natural and inevitable consequence of the increased expansive force of the steam, confined by an overloaded safety-valve, while she lay for fifteen or twenty minutes “ with boilers closed, and a surnace as hot as dry wood could make it."

“I have obtained direct evidence, that the valve was over

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loaded. Formerly, the machinery of the safety-valve was of more simple construction, as ordinarily made, than at present. It consisted of a simple lever, or steel-yard, with an adjustable weight, which was occasionally raised by the engineer, by means of a cord attached to the extreme end of that lever, and passed over pulleys. This gave the engineer no power of holding down the valve. In the present more complicated and more objectionable plan, a long rod, or axis, running from the engineer's station, at right angles to the steel-yard, engages it by a short arm for that purpose, in such a manner, that, when the rod is twisted auger-like, it shall lift the valve in one direction, and hold it down in the other. This rod terminates at the other end, near the engineer's station, in a cross or T, like the handle of an auger ; but the two ends of this cross-piece are not alike, one is a handle by which to raise the valve, and the other is a hook intended expressly for the application of extra weights." - Report, &c. p. 52.

Satisfactory evidence was procured to show that this hook, significantly called the death-hook, was loaded with a weight, which would have required a pressure of steam of two hundred and thirty-seven pounds to the square inch to raise it.

“It appears from the above, that safety-valve is a nickname. There is a valve, which can be raised to let off steam ; but, when thus indefinitely loaded, it scarcely affords safety." Ibid., p. 53.

The evidence that the boilers were not empty, and consequently were overheated at the time of the explosion, is we think conclusive. The following fact, establishing this position, cannot be explained away.

Jpon repairing to the scene of the casualty,

The first point to which Mr. Tift drew my attention, was the fact, that the leaden collets, called grummets, which lie under the heads of the bolts connecting the boilers with each other, were not melted. These leaden collars are inside of the boilers, and at a part exposed outwardly to the fire, and at the same time so near the top of the water as to be first exposed to great heat when the water should become too low..... The fact, that the lead was not melted, was fully ascertained in the fragments of the boilers, of about fifty to sixty square feet, lying part of the way up the bank, opposite the place of explosion.'

But yet so inveterate is the prejudice in favor of the “notion, ” (referred to at page 31,)“ that the only thing necessary for safety is, that they should keep water enough in the boilers,” that this pregnant fact failed to convince many of

the spectators; and the belief is now prevalent on the river, that the Moselle exploded because her boilers were empty,

from the effect of gas generated upon the sudden admission of water, on the starting of her forcing-pump. “Why not,

. says the Doctor, “call it witchcraft?

This explosive gas, so much talked of, has, by the way, never yet been detected by the researches of science.

"Hot iron will decompose water and evolve hydrogen, but hydrogen alone is not explosive ; besides, the heat required for this decomposition is far above that attained in cases of explosions attributed to the

presence of gases. Nor is hydrogen explosive when mixed with oxygen, unless within certain limits not likely to be attained in steam-boilers. Theoretically, gaseous explosions of boilers are improbable, and, practically, they have been quite disproved." - Report, p. 36.

Professor Hare, in his answer to the Secretary of the Treasury, says;

“Every well-informed chemist knows, that in copper boilers bydrogen could not be generated, and that in iron boilers its generation would require a heat of which the consequent pressure would be irresistible by the strongest vessels, especially as the tenacity of the vessels would be much lessened ; that, if hydrogen were generated, it c vuld not explode per se ; that the only imaginable agent which could enable it to explode would be the atmospheric oxygen, which could have no adequate access ; that, if atmospheric air were present, the intermixture of the steam would so impair its efficacy, that inflammation could scarcely ensue, and that of course, no explosion could take place." - Letter, &c. p. 383.

Why need we, as a palliative for recklessness or folly, look for some latent and mysterious cause, when a rational deduction from well-known and intelligible facts will furnish a solution ?

“ The expansive force of steam produced in a close boiler containing a sufficient supply of water increases as the heat increases, but not at the same rate, the force increasing faster than the heat.” Report, p. 29.

The expansive force, it appears from experiments, is doubled by every fifty additional degrees of heat. Now, in the case before us with the safety-valve loaded beyond the possibility of being raised, and furnaces heated by the continual introduction of dry wood, what difficulty is there in coming to the conclusion, that the boilers, by the increasing VOL. L. NO. 106.

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pressure of the steam, were strained to their utmost limit of tension, and that the jar occasioned by the starting of the machinery produced the explosion ? The result of a jar, or slight concussion, upon bodies so strained, is well explained by several apt illustrations, at page 38 of the Report.

We have dwelt, somewhat at length, upon the history of this casualty, both because of its prominence on the list of disasters, and because we thought it well adapted to show the ignorance and wantonness of men to whose charge are sometimes committed the lives of so many of their fellowcreatures, the blindness and infatuation of passengers, and the gauge by which steamboat performances are generally measured.

Whether it is possible to guard against these manifold accidents, and to render steamboat travelling as safe on the Western waters as it has become generally at the East, — is a question, in answering which a great diversity of opinion may well exist. It appears to us, that the dangers we have been endeavouring to portray, so many of which are intrinsic to the Westeru rivers, will for a long time prevent the attainment of the same precision and safety as now characterize the performances of boats on the Eastern waters. But of the effect of care and vigilance in diminishing risk, we have abundant proof. We know a captain, who, during sixteen years of service has never had a man scalded, nor ever met with any worse accident than the breaking of a shaft. He never allows a man in his employ to play at cards on board of his boat, and is careful to select men of temperate habits. We were gratified some time since to hear him say, that he was about building a boat, from which the bar (that fruitful source of accident and death) was to be utterly excluded. Whenever this example shall be universally followed, a moiety at least of the danger in these boats will cease. It is a well-known fact, that accidents but seldom happen to the larger and more valuable boats, and the reason is obvious ; the amount of capital invested in them compels their owners, in the selection of commanders and crew, to exercise a care which a sense of responsibility, and the dictates of humanity, in all other cases demand of them in vain.

We were long of the opinion, that public sentiment, the great corrector of all abuses in this country, bestowing patronage only on boats that were carefully managed,

would, by addressing itself to the self-interest of boat-owners and captains, gradually bring about the change so much to be desired. But the experience of the last few years, during which accidents have been fearfully increasing in frequency and magnitude, seems to forbid us to look to this source with much hope of its speedy or effectual operation. The reason for this must be looked for, parıly in the ignorance of the travelling public as to what are the qualifications of the boats offered to their choice. A stranger reaches Pittsburg, perhaps an emigrant with his family, who has never seen a Western steamboat. He repairs to the landing, and finds one or two boats about to start for his place of destination. He goes on board, and sees in the cabin spacious and showy accommodations ; while the elevation above the water, and the entire separation of the passengers' apartments from the machinery and dirt of the deck naturally please him ; but any correct information as to the character of the captain, the competency of the engineers and pilots, the condition of the hull, the safety of the engine or boilers, is as much out of his reach, as though he were on the other side of the mountains. For we can hardly suppose him so gullible as to place any reliance on the framed certificate (of an inspector who knows no more about it, nor has much more chance of knowing, than himself, which sets forth, that, some six months before, hull and engine were in good order, and "every way suitable for the transportation of freight and passengers."

He asks for information, and the first person whom he encounters is perhaps an agent for the very

boat whose character he wishes to learn ; and he is assured, that, by a fortunate chance, he now has an opportunity of embarking on board the very best boat, under the charge of the most careful captain, on the Western waters. Ile steps into a commission store, belonging most likely to one of the owners of the same boat, and the same agreeable information is repeated. Nor, if bis information be erroneous, is he likely ever to be undeceived ; for he will find but few who know any thing about it, and they who know aught unfavorable are unwilling

Or, suppose the traveller has some experience in the matter, and would give the preference to ceriain boats ; they may be a thousand miles off, in a different trade ; or the time of their arrival may be uncertain. Few are willing to incur the expense and delay of waiting ; and the conse

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