with the usual appendant machinery. The 193 feet, divided by twelve, give 16 mill seats, each driving 11 pair of six feet millstones, making in all 176 pair, each pair equal to 2000, making 352,000 spindles, or 1760 horse powers. The same course of reasoning and calculation having been applied throughout, it will not be necessary to repeat it for each stream separately.

Secondly, beyond ten and within twenty miles. Five miles from Ellicott's upper mill, at the junction of the north and west branches, the elevation of this stream, by the levelings for the Potomac canal, is 269 feet above the tide; deducting from this the 193 feet below Ellicott's upper mill, the fall of these five miles is ascertained to be 76 feet, and the slope of the country warrants us to assume the same fall for the remaining five miles, which gives the whole fall 152 feet within the limits assigned in our calculations. We here assume that the stream possesses only half the power, which it has in the inner circumference, although both the branches are only considered as one. Therefore, 152 feet fall yield 123 mill seats, each driving 5 pair of mill stones; equal to 69 pair; equal to 139,000 spindles, or 697 horse powers.

No. 2. Great Gunpowder Falls.

At the distance of twentyone miles, on the York turnpike road, the elevation of this stream has been ascertained by the levelings for the Susquehanna canal to be 3263 feet. The junction of the two branches is about a mile below this point, and exactly on the line of our circumference of twenty miles. An elevation of 300 feet may therefore be safely assumed for this point. A small portion only of this stream approaches within ten miles, including General Ridgely's works at Hampton; all the rest flows within the outer circumference. The power of the stream in its whole extent is equal to that of the Patapsco below Ellicott's mills, and the calculations have been made accordingly.

No. 3. Little Gunpowder Falls.

The whole of this stream lies between the inner and outer circumference; its fall has not been ascertained by any measurement, but it is believed that it may be safely compared to Jones' Falls in every respect, by allowing it a total fall of 250 feet, with a capacity of two pair of six feet millstones for every twelve feet fall.

No. 4. Jones' Falls

Is entirely within the circumference of ten miles, its total fall is ascertained to be 259 feet, and its capacity two pair of six feet millstones for every twelve feet fall.

No. 5. Gwinn's Falls,

Within ten miles, has a fall of 372 feet, with a capacity of two pair of six feet millstones for every twelve feet fall.

Beyond ten miles, it contains William Owing's three mills, each with a fall of 20 feet, and competent with that fall for one pair of six feet millstones, the year round, making 3 pair for our standard of twelve feet fall.

No. 6. Herring Run

Has a fall of 150 feet within five miles of the city, but the entire capacity of the whole stream does not exceed five pair of six feet millstones the whole year round, making for our standard of twelve feet fall, pair.

No. 7. Union Run

Is a branch of Jones' falls, and lies entirely within five miles of Baltimore; its whole fall is 106 feet, and its entire capacity two pair of six feet millstones, making th pair for our standard.

No. 8. Winter's Run

Lies near the outer boundary of the greater circumference, it has a fall of 150 feet, with a capacity of two pair of six feet millstones for every twelve feet fall.

Nos. 9, 10. Patuxent River.

Although this river discharges itself into the Chesapeake Bay at a very great distance from Baltimore, yet the most important part comes considerably within the outer circumference assumed for our limits. The junction of the two branches is just 20 miles from Baltimore; from this point, the north branch on which the Savage cotton factory is situated, lies entirely within our limits. The head race of this factory, according to the levelings for the Potomac canal, is 181 feet above the tide. Deducting 30 feet for the fall of the river below the junction, and adding 100 feet for the millseats known to exist above the Savage factory, we have a total fall of 250 feet for this branch, to which may be justly assigned, a power of 21 pair of millstones for every twelve feet fall.

The western or main branch of the Patuxent, flows within our limits, for a course of fifteen miles. From the same data as above, we may assign to this course a fall of 160 feet, with a power of four pair of six feet millstones for every twelve feet fall.

QUARTERLY LIST OF NEW PUBLICATIONS.

AGRICULTURE.

The Massachusetts Agricultural Repository and Journal. Vol. VIII. No. 3. January, 1825.

Nature and Reason Harmonised in the Practice of Husbandry. By the late John Lorain. Philadelphia. Carey and Lea.

Address delivered before the Philadelphia Society for promoting Agriculture, at its Annual Meeting on the 18th of January, 1825. By Bobert Vaux. 8vo. pp. 28. Philadelphia.

The author first draws a short sketch of the history and progress of agriculture from the earliest times; but the chief part of his discourse is devoted to the agriculture of Pennsylvania. He describes the early modes of cultivation in that state, and follows step by step the improvements, which have been gradually taking place. In conclusion he makes some excellent remarks on the importance of moral, literary, and scientific instruction in an agricultural country, as promoting both the science of husbandry, and the happiness of the people.

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Conversations on Natural Philosophy, in which the Elements of that Science are familiarly explained, and adapted to the Comprehension of young Pupils. Illustrated with Plates. By the Author of Conversations on Chemistry. Seventh Edition, with numerous Improvements. By Rev. J. L. Blake. Boston.

Lectures on the Adulteration of Food and Culinary Poisons in general, and of Adulteration in sundry Chemical Preparations, &c. in Medicine and the Arts, with the Means of discovering them, and Rules for determining the Purity of Substances; delivered in the United States Military Academy. By James Cutbush. 12mo.

The Mysteries of Trade, or the great Source of Wealth; containing Receipts and Patents in Chemistry and Manufacturing; with Practical Observations on the Useful Arts, original and compiled. By David Beman. 8vo.

The American Journal of Science and Arts. Vol. IX. No. 1.

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Elements of Astronomy, illustrated by Plates for the Use of Schools and Academies, with Questions. By John H. Wilkins,

A. M. Third Edition. Boston. Cummings, Hilliard and Co.

12mo.

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Musical Biography, or Sketches of the Lives and Writings of Eminent Musical Characters, interspersed with an Epitome of interesting Musical Matter. By John R. Parker. 8vo.

Outlines of the Principal Events in the Life of General Lafayette. From the North American Review. 8vo. pp. 64. Bos

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Biography of the Signers of the Declaration of Independence. Vol. V.

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A Sketch of the Botany of South Carolina and Georgia. Vol. II. No. 6. By Stephen Elliott.

COMMERCE.

Reply of the Committee of Merchants of Philadelphia, to the Memorial of the Auctioneers, lately presented to Congress. pp. 15.

8vo.

A Brief View of the Law relating to Transactions between Principals, and Factors, or Agents. A Memorial to the Legislature, praying for an Alteration of the Law, &c. Respectfully addressed to the Members of the Senate and Assembly of New York.

pp. 14.

EDUCATION.

8vo.

Comparative View of the Systems of Pestalozzi and Lancaster; in an Address delivered before the Society of Teachers in the City of New York. By Solyman Brown, A. M.

Essay on the Study and Pronunciation of the Greek and Latin Languages. By Wm. White, A. M. Philadelphia. 8vo. pp. 24. A. Finley.

The English Teacher, or Private Learner's Guide; containing a New Arrangement of Murray's Exercises and Key, &c. Designed to accompany and match with the Boston Stereotype Edition of Murray's Exercises prepared for the Use of Schools. By Israel Alger, Jr. A. M. Teacher of Youth. Boston. Lincoln and Edmands.

Murray's English Exercises, consisting of Exercises in Parsing, &c. Revised, prepared, and particularly adapted to the Use of Schools; being a Counterpart to the English Teacher. By Israel Alger, Jr. A. M. Boston. Lincoln and Edmands.

The American Arithmetic, in which the Science of Numbers is theoretically explained and practically applied, &c. Also a System of Book Keeping by Single Entry. Designed for the Use of