AMERICAN HOMES AND GARDENS 



August, 1908 



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II LATurvb 



GURNEY HEATERS, measured by quality, economy and 

 efficiency, are the standard of value. 

 <J They are made of the best materials and by the highest grade of 

 mechanical and engineering skill; constructed under these conditions, 

 they are unequaled in durability. 



<J There is also complete combustion of fuel and no waste of heat 

 units, thus insuring great economy. 



«I The GURNEY HEATER, made either for hot water or steam, 

 distributes the heat evenly and with a certainty that gives complete 

 satisfaction to the user. 



<J Easily installed in old or new buildings they appeal to those who 

 want to eliminate extra care and waste, or who want greatest value 

 for amount expended. 

 fl Send for illustrated catalogue. 



GURNEY HEATER MFG. CO. 



188-200 Franklin St., Corner Pearl St., BOSTON, MASS. 

 NEW YORK BRANCH, 12 East 42d Street 



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New Papers on 



Concrete 



Reinforced 

 Concrete 



Concrete 

 Building 

 Blocks 



Scientific American Supplement 1543 contains an 

 article on Concrete, by Brysson Cunningham. 

 The article clearly describes the proper com- 

 position and mixture of conciete and gives the 

 results of elaborate tests. 



Scientific American Supplement 1538 gives the 

 proportion of gravel and sand to be used in 

 concrete. 



Scientific American Supplements 1567, 1568, 1569, 

 1570 and 1571 contain an elaborate discussion 

 by Lieut. Henry J. Jones of the various systems 

 of reinforcing conciete, concrete construction, 

 and their applications. These articles constitute 

 a splendid text book on the subject of reinforced 

 concrete. Nothing better has been published. 



Scientific American Supplement 097 contains an 

 article by Spencer Newberry, in which practical 

 notes on the proper preparation of concrete are 

 given. 



Scientific American Supplements 1568 and 1569 



present a helpful account of the making of 

 concrete blocks by Spencer Newberry. 



Scientific American Supplement 1534 gives a 

 critical review of the engineering value of re 

 inforced concrete 



Scientific American Supplements 1547 and 1548 



give a resume in which the various systems of 

 reinforced concrete construction are discussed 

 and illustrated. 



Scientific American Supplements 1564 and 1565 



contain an article by Lewis A, Hicks, in which 

 the merits and defects ot reinforced concrete are 

 analysed. 



Scientific American Supplement 1551 contains the 

 principles ot reinforced concrete with some 

 practical illustrations by Walter Loring Webb. 



Scientific American Supplement 1573 contains an 

 article by Louis H. Gibson on the principles of 

 success in concrete block manufacture, illus- 

 trated. 



Scientific American Supplement 1574 discusses 

 steel for reinforced concrete. 



Scientific American Supplements 1575, 1576 and 



1577 contain a paper by Philip L. Wormley, Jr., 

 on cement mortar and concrete, their prepara- 

 tion and use for farm purposes. The paper ex- 

 haustively discusses the making ot mortar and 

 concrete, depositing of concrete, facing concrete, 

 wood forms, concrete sidewalks, details of con- 

 struction of reinforced concrete posts, etc. 



Scientific American Supplement 1583 gives valu- 

 able suggestions on the selection of Portland 

 cement for concrete blocks. 



Scientific American Supplement 1581 splendidly 

 discusses concrete aggregates. A helpful paper. 



Scientific American Supplements 1595 and 1596 



present a thorough discussion of sand for mortar 

 and concrete, by Sanford E. Thompson. 



Scientific American Supplement 1586 contains a 

 paper by William L. Larkin, on concrete mixing 

 machinery in which the leading types of mixers 

 are discussed. 



Scientific American Supplement 1626 publishes a 

 practical paper by Henry H. yuimby on con- 

 crete surfaces. 



Scientific American Supplement 1624 tells how to 

 select the proportions tor concrete and gives 

 helpful suggestions on the treatment of con- 

 crete surfaces. 



Scientific American Supplement 1634 discusses 

 forms for concrete construction. 



Scientific American Supplement 1639 contains a 

 paper by Richard K Meade, on the prevention 

 ot freezing in concrete by calcium choloride. 



In Scientific American Supplement 1605 Mr. 



Sanford E. Thompson thoroughl} - discusses the 

 proportioning of concrete. 



Scientific American Supplement 1578 tells why 

 some tail in the concrete block business. 



Scientific American Supplement 1608 contains a 

 discriminating paper by Ross F Tucker on the 

 progress and logical design of reinforced con- 

 crete. 



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EACH NUMBER of the SUPPLEMENT COSTS 10 CENTS. A SET of PAPERS CON- 

 TAINING ALL THE ARTICLES ABOVE MENTIONED WILL BE MAILED for $3.40 



Order from vour Newsdealer or from 



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MUNN & CO., Publishers, BRoiSW, New York City 



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North American Trees. By Nathaniel 

 Lord Britton, with the assistance of John 

 Adolph Shafer. New York: Henry 

 Holt & Co. Pp. 10+894. Price, $7.00. 



Our Trees: How to Know Them. By 

 Clarence M. Weed. Photographs from 

 nature. Philadelphia: J. B. Lippincott 

 Co. Pp. 295. Price, $3.00. 



Handbook of the Trees of the North- 

 ern States and Canada East of the 

 Rocky Mountains. By Romeyn Beck 

 Hough. New York: Harper & Brothers. 

 Pp. 10+470. Price, $8.00. 



These three books sum up, in a very com- 

 plete and practical way, the latest knowledge 

 relative to American trees. Each has its own 

 particular field, each makes its own especial 

 appeal to the reader and student as well as to 

 the nature lover. Each has its own scope and 

 presents its subject in its own way. Separately 

 and together they constitute a rich addition to 

 our tree literature, and each must find a wel- 

 come space on the shelves of the tree lover. 



It is a wholesome indication of popular and 

 widespread interest in trees that three such 

 notable books on this subject should appear 

 from three different presses at the same time. 

 Books of this description are expensive to 

 manufacture, since a very abundant illustra- 

 tion is necessary to render their contents avail- 

 able. All of these books are lavishly illus- 

 trated, and it is quite possible to obtain a 

 tolerable knowledge of trees from the mere 

 study of their plates alone. This in itself is 

 a boon of no slight value, since familiarity 

 with the aspects of trees is a first step to a real 

 knowledge of them and an immense help to 

 their true appreciation. 



Dr. Britton's monograph is a thoroughly 

 scholarly production, and is designed to de- 

 scribe all the kinds of trees known to grow 

 independently of planting in North America, 

 north of the West Indies and Mexico, and 

 to illustrate them by figures showing the 

 character of foliage, flowers and fruit. These 

 figures are drawings, and have the character 

 and value of technical illustrations; they are. 

 however, supplemented with photographs il- 

 lustrating the general aspect of certain species. 

 Such illustrations are less numerous than the 

 botanical drawings, and it is on these that the 

 illustrative value of the work chiefly depends. 

 Prepared with great care, and in most cases 

 expressly for this work, these illustrations may 

 be depended upon as a ready means of identify- 

 ing our trees by their foliage, flowers and 

 fruit. 



The scope of the book is necessarily very 

 large, and the number of trees described and 

 illustrated is immense. The text, therefore, is 

 obviously restricted to the most condensed de- 

 scriptions. These, however, will be found 

 entirely adequate, and especial care has been 

 taken to present them in non-technical words, 

 for the book makes a wider appeal than to the 

 technical botanist. The author has been com- 

 pletely successful in producing a book that is 

 notable in every way, and which must, for 

 some time to come, remain the standard mono- 

 graph on its subject. 



Dr. Weed's book is based on more popular 

 models. It does not aim to cover the whole 

 immense subject of American trees, but in 

 discussing and illustrating the more common 

 kinds it covers the subject sufficiently well to 

 make it an excellent medium for acquiring an 

 intimate acquaintance with most of them. 



