Trees of Pennsylvania

Trees of Pennsylvania

Author: Charles Fergus

Publisher: Stackpole Books

Published: 2002-08-01

Total Pages: 294

ISBN-13: 0811745562

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Common and uncommon tree species described in engaging detail. Covers trees found in small woodlots, deep forests, backyards, and reverting fields.


Nature's Flyers

Nature's Flyers

Author: David E. Alexander

Publisher: JHU Press

Published: 2004-11-17

Total Pages: 390

ISBN-13: 9780801880599

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'Nature's Flyers' is a detailed account of the current scientific understanding of the primary aspects of flight in nature. The author explains the physical basis of flight, drawing upon bats, birds, insects, pterosaurs and even winged seeds.


Spinning Flight

Spinning Flight

Author: Ralph D. Lorenz

Publisher: Springer Science & Business Media

Published: 2007-02-02

Total Pages: 369

ISBN-13: 0387472894

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More frisbees are sold each year than baseballs, basketballs and footballs combined. Yet these familiar flying objects have subtle and clever aerodynamic and gyrodynamic properties which are only recently being documented by wind tunnel and other studies. In common with other rotating bodies discussed in this readily accessible book, they are typically not treated in textbooks of aeronautics and the literature is scattered in a variety of places. This book develops the theme of disc-wings and spinning aerospace vehicles in parallel. Since many of the examples are recreational, anyone who enjoys these activities will likely find it profitable and enjoyable. In addition to spinning objects of various shapes, several exotic manned aircraft with disc planforms have been proposed and a prototypes built – these include a Nazi ‘secret weapon’ and the De Havilland Avrocar, also discussed in the book. Boomerangs represent another category of spinning aerodynamic body whose behavior can only be understood by coupling aerodynamics with gyrodynamics. The narrative, supported by equations and graphs, explains how the shape and throw of a boomerang relates to its trajectory. The natural world presents still other examples, namely the samaras or ‘seed-wings’ of many tree species, which autorotate during their descent, like a helicopter whose engine has failed. The flight performance of these spinning wings directly affects the dispersal and thus the evolutionary competitiveness of the trees concerned. Samara-type configurations are also considered for instrumentation and other payload dispersal applications. In short, the book discusses a range of familiar, connected, but largely undeveloped, topics in an accessible, but complete, manner. From the reviews of the first edition: "In his fascinating book Spinning Flight, Ralph Lorenz provides a rich feast of ... examples of spinning bodies ... . The book is well organized ... . The discussion in the book ... should be accessible to readers with some elementary understanding of aerodynamic principles. For the expert, the book is full of open problems ... . Its scope is extensive ... . In this respect, there may be something for everyone within its attractively designed cover ... ." (H. K. Moffatt, Nature, Vol. 444, December, 2006) "If you liked physics at school, then this book is for you. It concerns itself with flying objects that spin through the air, and even tells you how to impress your friends with the biomechanics of Frisbees. ... there is plenty of information at all levels, and the book has a wealth of detail that only an aerospace engineer like Lorenz could have come up with." (Len Fisher, BBC Focus, February, 2007)


Catalogue of the Phaenogamous and Vascular Cryptogamous Plants of Indiana (Classic Reprint)

Catalogue of the Phaenogamous and Vascular Cryptogamous Plants of Indiana (Classic Reprint)

Author: Charles R. Barnes

Publisher: Forgotten Books

Published: 2016-09-02

Total Pages: 48

ISBN-13: 9781333437121

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Excerpt from Catalogue of the Phaenogamous and Vascular Cryptogamous Plants of Indiana Noble. Explorations for several seasons have been made in Parke, Mont gomery, Tippecanoe, Carroll and Cass and for one summer in Allen, Wabash. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.