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Books and Periodicals 325The Most Popular Scientific Paper in the World

The Most Popular Scientific Paper in the World

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Established 1876.

Established 1876.

This journal is a separate publication from the Scientific American, and is designed to extend and amplify the work carried on by the parent paper. In size and general make-up it is uniform therewith, covering sixteen pages of closely printed matter, handsomely illustrated. It has no advertising pages, and the entire space is given up to the scientific, mechanical and engineering news of the day. It differs from the Scientific American in that it contains many articles that are too long to be published in the older journal, or of a more technical nature.

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Isometrical View Of Track

Isometrical View Of Track

Steel Faced Roads Solve the Problem

Cost No More Than Macadam And Need Practically No Repairs

The United States Department of Agriculture, Road Division, says:

" 1. - That the steel track wagon road can be built without greater cost in most cases, and probably with less cost in many cases, than any other hard and durable road.

" 2. - That it will last many times as long as any known material for road purposes, and with much less repair.

" 3. - That the power required to move a vehicle over the steel track road is only a fraction of the power required to move the same vehicle over any other kind of road."

This is stated after thorough investigation and from expert knowledge

Full information and details for domestic and foreign use, furnished upon application

Fully Adapted To Bridges, Wharves, Etc.

Steel Highway Track Construction Co.

Drexel Building, Philadelphia

Revised and Enlarged Edition

Revised and Enlarged Edition

The Scientific American Cyclopedia of Receipts, Notes and Queries

Books and Periodicals 330

15,000 Receipts. 734 Pages

Price $5.00 in Cloth. $6.00 in Sheep. $6.50 in Half Morocco.

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Twenty-third Edition

Experimental Science

By George M. Hopkins

Revised and Greatly Enlarged. Two Octavo Volumes. 1,100 Pages. 900 Illustrations. Cloth Bound, Postpaid, $5.00. Half Morocco, Postpaid, $7.00.

Experimental Science is so well known to many of our readers that it is hardly necessary now to give a description of this work. Mr. Hopkins decided some months ago that it would be necessary to prepare a new edition of this work in order that the many wonderful discoveries of modern times might be fully described in its pages. Since the last edition was published, wonderful developments in wireless telegraphy, for example, have been made. It was necessary, therefore, that a good deal of new matter should be added to the work in order to make it thoroughly up to date, and with this object in view some 200 pages have been added. On account of the increased size of the work, it has been necessary to divide it into two volumes, handsomely bound in buckram.