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unusal course also produced the erratic phenomenon of a "backing” wind holding steadily from ono direction (sco Toledo record) for forty hours. Mauy disastrous wrecks occurred, and it is worthy of note that several of the worst were in tlo vicinity of the “Narrows,” before mentioned, between Long Point and the American sloro near Erio and Dunkirk. The steamers Dean Richmond and Trocokca and the schooners C. B. Benson and Riverside were all lost during this storm, and all in the same locality-at these “Narrows." Seven lives were lost with each of the schooners, which were considered to be seaworthy boats, as both were in the grain trade. Not a soul was saved from the Richmond and but three from tho Jocokea.

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It will be observed that while few of the heights are accurate, they carry suficient reliability to warrant a general discussion of tho matter in the light of this crude data, and tho hopo that it will lead to the obtaining of more definite knowledge and perhaps moro sound conclusions. A discussion of other points of interest than those touched upon in this report, though tempting, is, I feel, hardly justified by the data now at hand.

It must also be noted that all data we have was recorded along tho south shore of the lake and that the times of record are not coincident, though generally nearly so.

Following now the profile of water anıl surface in connection with the above data, we find that in the West Basin tho fall in the funnel-shaped end, containing Monroe and Toledo, was 6.8 feet; in the open it was 5.3 feet. In the inain basin, immerli. ately wo pass tho Island barrier, tho fall was but 2.6 feet for all points until Cleveland is reached at the widest part of the lake. Here we find a fall of but 1.2 fect, and practically the same at Ashtabula. Between Ashtabula and Conneaut, a distance of 13 miles, we meet a solid wall of water 4.7 feet high, there having been a rise of 3.4 feet at Conneaut. At Erio the riso was 0.8 foot less than at Conneaut, and at Buffalo the highest point reached was 5.3 feet.

The question now at onco arises, do these surface heights along the sonth shore correctly represent the lieights of water in the lake? Assuming it to be so, that is, that the surface is level on each line normal to the shore, then the surplus water in the eastern end of the lake should be about equal to the deficiency in the west end. We find the line of no variation from the normal stage before and after the storm to have heen between Ashtabula and Conneant. The area west of this line is approxi. mately 7,000 square miles, that east of it, 3,000 square miles. In order to make tho two quantities equal, the proportion of fall to rise should be as 3 to 7. The record of fall being more numerous, covering larger territory and to a fair extent agreeing among themselves, we may assume a fall of 5.3 feet over 1,200 square miles, 2.6 feet over 1,800 square miles, 1.2 feet over 4,000 square miles, to equal a fall of 2.3 feetover 7,000 square miles; which would give, if our assumption is correct, an average rise of { of 2.3 feet = 5.4 over 3,000 square miles. This is not borne out by the data, as it is as large as the maximum height at Buffalo, and twice as large as that at Erie. To show its absurdity, we have really an average rise of perhaps 3.7 feet over 3,000 squaro miles, which leaves unaccounted for a body of water amounting to 16,000,000,000 of cubic feet, enough to supply tho ordinary ontflow of Niagara for 20 hours. This amount is beyond that already accounted for by the recorded rise at Buffalo, which by itself would scarcely double the outflow even while it lasted. When we consider the pressure which must have existed in connection with the change of elevation of 4.7 feet in 13 miles between Ashtabula and Conneaut, and consider also the immense volume of water displaced west of them and not found to the eastward, it suggests the idea of an enormous eddy or swirl, more or less forcible, in that portion of the lake, the current settiag down along the south shore and up along the Canadian side. The observations, though crude, seem to show conclusively that the surface of the lake is not level on the normal lines, but is much higher on the nortłı shore. This is borne out by the fact before mentioned that during tho height of the galo there is invariably a reflex current into the west point of the lake, too strong to allow of the belief that it is caused by the gravity of the “piled up” water overcoming the force of the wind. It is a fact that most of the Lake Erie wrecks during a westerly gale are in the vicinity of the “Narrows." In an easterly gale, when theso peculiar conditions do not exist, there is seldom a loss in that region.

Is it not possible that in these serious storms there are forces at work for Cestruction with which we are not familiar, and that a proper study would give the means for combatting them successfully!

I beg leave to suggest that the line of thought here touched npon is important enongh to warrant further and more accurate study on the basis of definite data. If the conditions here suggested do actually exist, it will be of vast importance to the navigation interests to know of them; and in order to gain the information for a moro thorough and accurate discussion, I respectfully recommend that steps be taken to have all light-keepers on Lake Erie record the height of water three tiines


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daily, together wit'ı ihe wind (lirections and velocities, and to have special instructions issueel that bey shall note any unusual conditions of weather or water. In any prolonged and severe storm, particularly those of April and October, they shall carefully note the extremes of water level and wind.

To be of any service in a further consideration of this subject, the Canadian authorities should be requested, through the proper channels, to cooperate fully.

I am thoroughly impressed with the idea that such observations will bear fruit of some importance at very slight expense. Very respectfully


Assistant Engincer. Lieut. Col. JARED A. Smith,

Corps of Engineers, V. S. A.

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Milwaukee, Wis., July 6, 1891. GENERAL: I have the honor to forward the accompanying plate * on which is continued the water level curve on Lake Michigan for the fiscal year ending June 30, 1891, and to inclose a letter from Lient. C. II. McKinstry, Corps of Engineers, giving the monthly mean water levels during the year.

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Very respectfully, your obedient servant,


Major of Engineers. Brig. Gen. THOMAS L. CASEY,

Chief of Engineers, 'U. 8. A.


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Milwaukee, Ilis., July 6, 1894. SIR: I have the honor to transmit herewith the water-level curves for Lake Michigan for the year 1893–94, from tridaily observations taken at Milwaukee, Wis., and Escanaba, Mich., with monthly reports of observers. Observations at Milwaukee were taken continuously throughout the year; at Escanaba they were discontinued from December 17, 1893, to March 18, 1894.

Following are the monthly means (feet and decimals below plane of reference) from which the curves wero plotted, the plano of reference being “high water of 1838."

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The “ reduction to the plano of reference” at Milwaukee is – 0.61 foot; that is, the zero of the gauge is 0.61 foot above the plane of reference. At Escanaba the reduction to the place of reference” was determined in 1877 to be - 0.76 foot

* Omitted.

(Report of 1876, Vol. II, p. 84; 1877, Vol. II, p. 1194), and the monthly means from that time until June, 1882, were corrected (reduced) by that amount. The observations from July, 1882, to June, 1887, were further reduced by 0.187 foot. (Report of 1887, p. 2417.) The observations from July, 1887, to June, 1892 (published in Report of 1892, p. 3130), and the observations for 1892–93 were reducel by 0.76 only. This was plainly an oversight, and I would respectfully suggest the desirability of making a further correction of — 0.187.

In July, 1893, the zero at Escanaba was tested by leveling from bench marks in the vicinity and was found to be 0.902 foot above the plane of reference. This correction (0.902 foot) was used in reducing the observations of 1893-'94. Very respectfully, your obedient servant,

C. H. McKinsTRY,

First Lieutenant of Engineers. Maj. JAMES F. GREGORY,

Corps of Engineers, U. &. A.




(For letter of transmittal see Appendix P P.)

Permanent gauges are established at Oswego Harbor and at Charlotte Harbor (at the inouth of the Genesee River), and each has been read three times per day during the year. They show the lake level to have been lower than usual at similar dates throughout the year.


This gauge was established in 1837 by the United States Engineer at Oswego at plane of extreme low water. The lake level has several times since been at this plane, but never below it. The gauge is cut on the bar bor face of the stone pier at the foot of West Third street, and is indicated by an iron plate cut to feet and tenths and bolted beside it.

The zero of the gange is referred to the top of an iron bolt in top of masonry of old Government stone pier 0.5 foot from east face of pier, 31 feet north of its intersection by the crib work wliarf, foot of the United States reservation at the foot of West Third street, Oswego, marked U.S. B. M. This bench mark is 7.75 feet above zero of gange.

The zero of gauge, on plane of extreme low water, is 244.21 fett above mean tide at New York. (See p. 609, Prof. Papers 24.)

Readings were taken daily at 7 a. in., 1 p. m., and 6 p. m. with observations of direction and force of wind. The daily means were taken, and a mean of three taken as a monthly mean.

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