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On Certain Phenomena connected with the Rise and Fall of the

Waters of the Northern Lakes. “During a residence of several summers on the borders of Lake Superior, my attention has been directed to the question, whether its waters were subject to any movement corresponding to the tidal action, and the result of my observations has been, to convince me that they do not rise and fall at stated periods, corresponding to the ebb and flow of the tide. On the other hand, abundant evidence exists that the waters are subject to extraordinary risings, which are independent of the influence of the sun and moon.

“ The late Governor Dewitt Clinton * published a memoir on this subject, which embodies many interesting facts. As that memoir is not readily accessible, we will extract such facts as are deemed most important. These risings attracted the attention of the earliest voyageurs in this region. La Hontan relates the following incident : -' On the 29th of May, 1689, we came to a little deep sort of a river, which disem. bogues at a place where the water of the lake (Michigan) swells three feet high in twelve hours, and decreases as much in the same compass of time. Our tarrying there for three or four days gave me an opportunity of making the remark.' Charlevoix,t who traversed the Lakes nearly a century ago, in reference to Lake Ontario says :- I observ. ed that in this lake, and I am told that the same thing happens in all the rest, there is a sort of flux and reflux, almost instantaneous, the rocks near the banks being covered with water and uncovered again several times in the space of a quarter of an hour, even if the surface of the lake was very calm, with scarce a breath of air. After reflecting for some time on this appearance, I imagined it was owing to springs at the bottom of the lake, and to the shock of their currents with those of the rivers which fall into them from all sides, and thus produce those intermitting motions.' Mackenzie, & who wrote in 1789, remarks :* A very curious phenomenon was observed at the Grand Portage on Lake Superior, for which no obvious cause could be assigned. The water withdrew with great precipitation, leaving the ground dry which had never before been visible, the fall being equal to four perpen

* Transactions of the New York Literary and Philosophical Society, Vol. II., Part I.

Journal Historique d'un Voyage de l'Amérique, L. XIII. Voyage to the Frozen and Pacific Oceans.

dicular feet, and rushing back with great velocity above the common mark. It continued thus rising and falling for several hours, gradually decreasing, until it stopped at its usual height.'

“Governor Clinton relates the following incident, which happened to Colonel Bradstreet, who commanded an expedition against the Western Indians in 1764: _In returning by way of Lake Erie, when about to land the troops one evening, a sudden swell of the lake, without any visible cause, destroyed several of his boats, but no lives were lost. This extraordinary event was looked upon as the precursor of a storm, and accordingly one soon occurred, which lasted several days.' The following occurrence, also related by him, took place on the British side of Lake Erie, on the 30th of May, 1823:- A little after sunset, Lake Erie was observed to take a sudden and extraordinary rise, the weather being fine and clear, and the lake calm and smooth. It was principally observed at the mouths of Otter and Kettle Creeks, which are about twenty miles apart. At Otter Creek, it came in, without the least previous intimation, in a swell of nine feet perpendicular height, as was afterwards ascertained, rushed violently up the 'channel, drove a schooner of thirty-five tons burden from her moorings, threw her upon high ground, and rolled over the ordinary beach into the woods, completely inundating all the adjacent flats. This was followed by two others of equal height, which caused the creek to retrograde a mile and a half, and to overflow its banks, where water was never be. fore seen, by seven or eight feet. The noise occasioned by its rushing with such rapidity along the winding channel was truly astonishing. It was witnessed by a number of persons. At Kettle Creek, several persons were engaged drawing a fish-net in the lake, when suddenly they saw the water coming upon them in the manner above described, and, letting go their net, they ran for their lives. The swell overtook them before they could reach the high bank, and swept them forward with great force, but being expert swimmers they escaped unhurt. The man who was in the skiff, pulling in the sea-line, was driven a considerable distance over the flat, and grounded upon a small eminence, where he remained until the water subsided. There were three successive swells, as at Otter Creek, and the effects were the same, with this difference, — the water rose only seven feet. In both cases, the lake, after the swells had spent their force, gradually subsided, and in about twenty minutes was at its usual height and tranquillity.'

“In 1828, Governor Cass instituted a series of experiments, at the head of Green Bay, to determine the changes in the water-level. These observations extended from the 15th of July to the 30th of August, and from them he infers that the changes in the elevation of the waters are entirely too variable to be traced to any regular permanent cause, and that consequently there is no perceptible tide at Green Bay which is the result of observation. And such, it appears to me, is the result of calculation, when the laws that regulate solar and lunar attraction are taken into view.'*

“ In the summer of 1834, an extraordinary retrocession of the waters took place at Sault St. Marie, the outlet of the lake. The river at this place is nearly a mile wide, and in the distance of a mile falls 18.5 feet. Its bed is sandstone, and, except in the immediate channel, the average depth of water is two and a half feet. The phenomenon occurred about noon. The day was calm, but cloudy. The water retired suddenly, leaving the bed of the river bare, except for a distance of thirty rods, and remained so for nearly an hour. Persons went out and caught fish in the pools formed in the depressions of the rocks. The return of the waters is represented as having been very grand. They came down like an immense surge, and so sudden was it, that those engaged in catching fish had barely time to escape being overwhelmed.

“ A similar phenomenon occurred twice on the same day in the latter part of April, 1842. The lake was free from ice, and no wind was prevailing in the vicinity.

“A few years previously, the precise period my informants could not designate, the current between the foot of the rapids and Fort Brady, which usually flows at the rate of two and a half knots an hour, was observed to set back. The water rose two feet or more, and the rate of the back.current was estimated at two knots an hour. Some of the soldiers at the fort, in order to satisfy themselves, jumped into a boat and rowed into the stream, when they found the current bearing them towards the foot of the rapids. How long this continued, my informants could not designate. A strong wind was prevailing from the south, but it was never before known to have produced such an accumulation of water. These facts I gathered from Mr. Hulburt, Ashmun, and Peck, old residents of Sault St. Marie.

* Remarks on the Supposed Tides and Periodical Rise and Fall of the North American Lakes, by Major (now Brigadier-General) Henry Whiting, American Journal of Science, Vol. XX., Part II. See also a paper by General H. A. S. Dearborn, Ibid., Vol. XVI.

“ I have witnessed numerous ebbings and flowings of the waters of Lake Superior.

"In the month of August, 1845, I was coasting in an open boat from Copper Harbour to Eagle River. It was late in the afternoon, and the lake was calm. To the northwest, the clouds indicated that different strata of air were moving in opposite directions. Mirage was beautifully displayed, and I was occupied in tracing out islands, with bold cliffs and spacious harbours, which had no real existence, when suddenly the water about a mile to the northwest was lifted up like a conical hill, to the height of apparently twenty feet, and swept towards the shore, diminishing in size as it advanced. The voyageurs saw it as it came rolling like a great breaker crested with foam, and headed the boat so as to cut the wave. It struck us without doing any injury, and was succeeded by two or three dead swells, when the lake resumed its former tranquillity. The cause which uplifted the water was local, and operated but for a moment. The swell could not, like the bore observed at the mouth of the Amazon, have resulted from opposing currents.

“ While at Rock Harbour, Isle Royal, in the summer of 1847, I witnessed, on one occasion, the alternate rise and fall of the water, recurring at intervals of ten or fifteen minutes, during an entire afternoon. The variation was from twelve to twenty inches. The day was calm and clear, but the barometer was falling. Before the expiration of forty-eight hours, a violent gale set in.

“On the 23d of July last, I went from Copper Harbour to Eagle River, where I arrived in the evening. The day had been calm, so much so that a sail was useless. In the evening, there sprang up an off-land breeze, as is frequent; but notwithstanding, I observed a strong current flowing into Eagle River. The next day, a storm came on which continued for several days.

“I have witnessed the ebb and flow of the water through the narrow inlets and estuaries, particularly at Copper Harbour, when there was not a breath of wind on the lake. Similar phenomena have been noticed on the Swiss Lakes Constance and Geneva, which are there called seiches.

“I have already given Charlevoix's theory to account for them. Volney supposed that Lake Ontario was the seat of an ancient volcano,

which occasionally afforded signs of being not entirely extinct, and Governor Clinton was inclined to connect them with earthquake movements. Professor Mather, who observed the barometer at Copper Harbour during one of these fluctuations, remarks : - As a general thing, fluctuations in the barometer accompanied Aluctuations in the level of the water ; but sometimes the water-level varied rapidly in the harbour, while no such variations occurred in the barometer at the place of observation.'*

“ As a general rule, these variations in the water-level indicate the approach of a storm, or a disturbed state of the atmosphere. The barometer is not sufficiently sensitive to indicate the sudden elevations and depressions, recurring, as they often do, at intervals of ten or twelve minutes, and the result of observations at such times may be regarded in some degree as negative. Besides, it may not unfrequently happen, that, while the effects are witnessed at the place of observation, the cause which produced them may be so far removed as not to influence the barometer.

“From all the facts, we are led to infer that these phenomena result, not from the prevalence of the winds acting on the water, accumulating it at one point and depressing it at others, but from sudden and local changes in the pressure of the atmosphere, giving rise to a series of barometric waves. The water, conforming to the laws which govern two fluids thus relatively situated, would accumulate where the pressure was the least, and be displaced where it was the greatest.

“ Again, as has been remarked by De la Beche, a sudden impulse given to the particles of water, either by suddenly increased or diminished pressure, would cause a perpendicular rise or fall, in the manner of a wave, beyond the height or depth strictly due to the mere weight itself. The difference in the specific gravity of the water of the lakes

* American Journal of Science, Vol. VI. (Second Series), July, 1848.

De la Beche (Survey of Cornwall), quoting from the MSS. of Mr. Walker, who has devoted much time to the phenomena of tides, says: -“He has found that changes in the height of the water's surface, resulting from changes in the pressure of the atmosphere, are often noticed in a good tide-gage before the barometer gives notice of any change. ..... If tide-gages at important dock-yards show that a sudden change of sea-level has taken place, indicative of suddenly decreased atmospheric weight, before the barometer has given notice of such change, all that time which elapses between the notices given by the tide-gage and barometer is so much gained, and those engaged with shipping know the value of even a few minutes before the burst of an approaching hurricane."

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