Uscellaneous Intelligence. 



the public and the sensationalism of the newspapers gave a char- 

 acter of finality never desired by Mr. Langley, were to him merely 

 members of a long series of experiments, as much so as any trial 

 of one of the small aerodromes or even of one of the earliest 

 rubber-driven models. Had his health and strength been spared, 

 he would have gone on with his experiments undiscouraged by 

 these accidents in launching and undeterred by criticism and mis- 

 understanding. 



"Moreover, it is to be borne in mind that Mr. Langley's con- 

 tribution to the solution of the problem is not to be measured 

 solely by what he himself accomplished, important as that is. 

 He began his investigations at a time when not only the general 

 public but even the most progressive men of science thought of 

 mechanical flight only as a subject for ridicule, and both by his 

 epoch-making investigations in aerodynamics and by his own 

 devotion to the subject of flight itself he helped to transform 

 into a field of scientific inquiry what had before been almost 

 entirely in the possession of visionaries." 



2. A Treatise on Hydraulics; by Hector J. Hughes, Assist- 

 ant Professor of Civil Engineering, Harvard University, and 

 Arthur T. Safford, Consulting Hydraulic Engineer. Pp. xiv, 

 505 with \11 figures and 5 plates. New York, 1911 (The Mac- 

 millan Company). — This treatise is a refreshing contrast to some 

 engineering books which have found publishers in this country 

 in recent years. There is no novelty in the contents, for the portion 

 of the field covered is that usually found in elementary treatises. 

 But in its clear style, logical treatment, orderly arrangement, and 

 full presentation of the latest and best researches in hydraulics, the 

 book is in many ways a model one. Chapters I-IV treat of 

 hydrostatics, covering the usual topics of fluid pressure and 

 equilibrium of floating bodies. Chapter V is a useful summary 

 of the principles of hydromechanics. Chapters VI, VII, VIII 

 treat of the measurement of flow of water by various forms of 

 meters. The space given to applications of the Pitot tube is an 

 indication of its growing importance. The chapters on orifices, 

 nozzles and weirs follow in the order named. The chapter on 

 flow in pipes is marked by fullness of re'erence to original data. 

 This is a difficult subject, and if confusing to the student, it is 

 so because of the unsatisfactory state of the experimental data. 

 The chapters on hydraulic motors form a good introduction to 

 that subject. 



A feature of the book is a collection of problems at the end of 

 each chapter. There are tables, including logarithms, squares, 

 square roots, cubes, cube roots, areas and circumferences of cir- 

 cles, also logarithmic diagrams for several hydraulic formulas. 

 The tables will be useful in solving the problems in the book. In 

 view of the convenience of the slide for hydraulic calculations 

 the omission of reference to it is surprising. E. H. Lockwood. 



3. Pure Foods — Their Adulteration, Nutritive Value and 

 Cost ; by John C. Olsen, A.M., Ph.D. Pp. 210. Boston, 1911 

 (Ginn and Company). — This is a useful little book adapted to 



