« ZurückWeiter »
The breaking up of the ice in the rivers of North America is one of the most wonderful operations exhibited by nature on that Continent.
By the beginning of April, although the sun has attained very considerable power, yet the ice in the rivers is so thick, and its temperature so many degrees below freezing, that little or no effect is produced upon it in the middle of the stream. The banks, however, of the river, receiving heat from the sun, treacherously melt that portion of the ice which immediately touches them, and this operation continues until a space of blue water intervenes between the shore and the ice sufficient to prevent any one from passing on foot from the one to the other, and yet, long after this period, the ice in the middle of the stream remains strong enough to bear artillery or carriages of any weight.
Now, it is evident that, if a river throughout its course were straight and of equal breadth, the current, without waiting until the sun should melt the ice, would carry it bodily away into the ocean so soon as the banks ceased to hold it.
Rivers, however, being more or less tortuous, and containing generally little islands and rocks, it became necessary for Nature to resort to an admixture in about equal parts of fair means and foul, or, in other words, to combine the persuasive powers of the sun with the rude violence of the torrent, and thus the dense stratum of ice which covers the surface of the river finds itself between two powerful enemies, one of which, by the constant application of heat, is trying to melt it, while the other, as it glides beneath it, is exerting a never-ceasing effort to drag it towards the sea. Any one who in swimming down a stream has ever chanced to grasp the branch of a tree overhanging the banks, has no doubt found it almost impossible to hold on; indeed if merely the palm of the hand be applied to the surface of running water, a rude guess may be made of the force a large river throughout its whole course must exert against a covering of ice which, standing stock still, refuses to partake of its course.
As the sun strengthens, the velocity and power of the current is hourly increased by the melting of the snow, which, by wrenching the ice upwards, isolates it, excepting at particular bends and turns of the river, that retain or jam the whole mass.
At these fortresses, as they may be termed, the pressure on the ice becomes immense; bit after bit breaks, until, each obstruction having given way, the whole mass is retained at some single point only. This last conflict between the elements of nature is truly terrific; fields of ice are forced upon the land, and then, grinding, squeezing, undermining, and raising each other, form impending rocks from 50 to 80 feet high! While the resistance of the ice is daily decreasing, the strength of the never-tiring current is hourly increasing, until by the swelling of the water the ice is either lifted above the insular obstruction that impeded it, or, unable any longer to resist, it is forcibly rent asunder. The hour of victory has now arrived, the spring of another new year has once again conquered the winter; the liquid water has overcome its frozen enemy, and the whole of the ice, writhing and breaking up in all directions, like a vanquished army, at first slowly surrenders its position, and then by a "sauve-quipeut" movement retreats in confusion proportionate to its mass.
I twice happened to succeed in witnessing the breaking up of the ice of the Humber, a small river in the neighbourhood of Toronto. The floods which had wrenched up the ice had floated a large quantity of timber of every possible description, and, as soon as the great movement commenced, these trees and the ice were hurried before my eyes in indescribable confusion. Every piece of ice, whatever might be its shape or size, as it proceeded, was either revolving horizontally, or rearing up on end until it reeled over; sometimes a tree, striking against the bottom, would slowly rise up, and for a moment stand erect as if it grew out of the river; at other times it would, apparently for variety's sake, stand on its head with its roots uppermost and then turn over; sometimes the ice as it proceeded would rise up like a house and chimneys, and then, rolling head over heels, sink, and leave in its place clear water.
In a few hours, however, this turmoil was completely at an end, the torrent had diminished, the stream had shrunk to its ordinary limits, and nothing remained to tell of the struggle and the chancemedley confusion I had witnessed but some white little islands of ice, intermixed with dark masses of timber, floating off the mouth of the river in the deep blue lake.
In the different regions of the globe it has been my fortune to visit, I have always experienced great pleasure in pausing for a few minutes at the various spots which have been distinguished by some feat or other of British enterprise, British mercy, British honesty, British generosity, or British valour.
About the time I was in Canada a trifling circumstance occurred on the breaking up of the ice, which I feel proud to record.
In the middle of the great St. Lawrence there is, nearly opposite Montreal, an island called St. Helens, between which and the shore the stream, about three quarters of a mile broad, runs with very great rapidity, and yet, notwithstanding this current, the intense cold of winter invariably freezes its surface.
The winter I am speaking of was unusually severe, and the ice on the St. Lawrence particularly thick; however, while the river beneath was rushing towards the sea, the ice was waiting in abeyance in the middle of the stream until the narrow fastness between Montreal and St. Helens should burst and allow the whole mass to break into pieces, and then in stupendous confusion to hurry downwards towards Quebec.
On St. Helens there was quartered a small detachment of troops, and, while the breaking up of the ice was momently expected, many of the soldiers, muffled in their great-coats, with thick storm-gloves on their hands, and with a piece of fur attached to their caps to protect their ears from being frozen, were on the ice employed in attending to the road across it to Montreal.
After a short suspense, which increased rather than allayed their excitement, a deep thundering noise announced to them that the process I have described had commenced. The ice before them writhed, heaved up, burst, broke into fragments, and the whole mass, excepting a small portion, which, remaining riveted to the shore of St. Helens, formed an artificial pier with deep water beneath it, gradually moved downwards.
Just at this moment of intense interest, a little girl, the daughter of an artilleryman on the island, was seen on the ice in the middle of the river in an attitude of agony and alarm. Imprudently and unobserved she had attempted to cross over to Montreal, and was hardly half-way when the ice, both above, below her, and in all directions, gave way. The child's fate seemed inevitable, and it was exciting