raine, and is now in operation. The results obtained in this way present fewer objections, and address themselves to the apprehension of every mind. The water that flows down the creek is obviously the available water, after having been subjected to evaporation, absorption, percolation, and every other conceivable cause of loss, so that the only correction to be made is the difference between the evaporation from the surface of the reservoir and that from the land submerged, because as the creek is gauged before the reservoir is filled, it appears to give too much-but on the other hand the area submerged is greater than that of the water, and the bottom being horizontal is most favorable for evaporation, so that the two would nearly balance, and even this correction may be omitted, and the quantity flowing down the creek taken as the available supply.

No one, I suppose, will doubt that water passing down a stream may be collected in a reservoir. The quantity of available water once obtained, your engineers can shew that it is among the simplest applications of their science, to construct an embankment or dam across the gorge of the valley that shall retain the whole, or so much of this water as shall be required for the supply of the summit level with all its contingencies.

It is well known that many of the most important canals of the world have their summit levels supplied from reservoirs, and it would be easy to point out numerous instances where rain water thus collected has been applied to economical uses on a very large scale. I shall content myself with one-the Shaw's Water Works.

At

The inhabitants of Greenock were anxious to procure a supply of water for domestic use. Engineers were employed, who examined the scanty streams in the vicinity, and reported unfavorably. length Mr. Thom examined the surrounding country, calculated the supply of rain water that could be economized, and astonished the good people of Greenock by shewing that "not only water sufficient for domestic and municipal purposes might be brought in, but that water power might be made available for mechanical purposes to a very great amount. His scheme has been carried into effect. calculations have been more than borne out, and the rapid rise of Greenock as an emporium of commerce and industry is, in no small degree, due to the bold foresight of the engineer of the Shaw's Water Works."

His

Dr. Kane, the eminent chemist, who was himself investigating this question for Ireland, writes still further:

"Anxious to obtain information as to the actual condition and performance of these remarkable Water Works, and unable personally to visit Scotland, I have to thank one of the most eminent men that country has presented to the practical sciences, for a note descriptive of the power that is now produced by the water so economized. Mr. Scott Russell replied to my enquiries in the following words:

48

'MY DEAR SIR,

'I had hoped to have been able to get a full and very satisfactory account of the Shaw's Water Works, drawn up for you by a competent engineer resident on the spot; but I find that so many delays are occurring to prevent this, that I now write to beg you will not calculate upon it; had my own time permitted I should have done so myself, but now, just when I might have hoped for leisure, I am taken from home.

'I have, however, procured a copy of a now scarce pamphlet, printed some thirteen or fourteen years ago, before the works were finished, giving some account of them as proposed. I may now add for your information, that everything predicted has been satisfactorily and fully accomplished; that the company now divide a fair per centage on their capital, even though at present only one-half of the capabilities of the reservoir are employed. There has in all years been an abundant supply.

'I may add, that the sole supply of water is from the fall of rain, and that the artificial lake has been created in a place where formerly there were only slender mountain rivulets.

"The guaranteed and realized supply of water amounts to 2,500 cubic feet per minute per 310 days per annum.

'J. SCOTT RUSSELL.'"

With best wishes for the success of the noble work in which you are engaged,

I am, Sir,

With much respect,

Richmond, November 6th, 1851.

Your obd't serv't,

M. TUOMEY.

7,108,163.4 48,686 125,653 7,640,263 52.331 146,442.4 8,588,821 155,950.7 8,998,032 61,630 175,210.2 10,319,149 70,680 177,381.7 9,708,415 66,496 174,614.3

[No. 4.]

Statement shewing the Quantities of the Principal Articles Conveyed on the Canal of the James River and Kanawha Company, during the several
periods specified.

[No. 8.]

Amount of Toll received upon the James River and Kanawha Canal on the following Articles, from the 1st of October 1848 to the 1st of October 1849.