72 . REVIEWS.

REVIEWS.

Minerals in Pastures and their relation to Animal Nutrition. By J. B. Orr, D.Sc., M.D., with the assistance of Helen Scherbatoff. From the Reid Library, Rowett Research Institute, Aberdeen. London: H. K. Lewis & Co., Ltd., 1929. Pages 150, Royal 8vo. Price lOs . 6d.

This work embodies the results of an endeavour to ascertain, by a search of the literature on the subject and a questionnaire addressed to the various Governments within the Empire, to what extent deficiency of minerals in pastures was the cause of malnutrition in cattle and sheep. The earlier chapters are devoted to a general consideration of the mineral content of pastures and the factors affecting the same, including the species and stage of growth of plants, the climatic conditions, and the nature of the soil. The bulk of the book sets out what has been ascertained regarding the occurrence of " defici­ency diseases " in cattle and sheep in different parts of the world, and a special chapter is allotted to such diseases in horses. As the work shows, the loss inflicted by deficiency diseases does not constitute the whole of the evil that may be caused by feeding animals on grass or hay with a defective mineral content, for the presence of the essential minerals in adequate amount is an important factor in determining the nutritive value of the pasture. It is a noteworthy fact that in the comprehensive survey which the work gives of the occurrence of deficiency diseases throughout the world, there is very little evidence that they are of serious economic importance in Great Britain, with the possible exception of certain tracts of mountain pasture in Scotland. An example of evidence that needs confirmation is the statement (p. 109) that the administration of potassium iodide to mares prevented joint-iII in foals in a stud in the South-'west of Scotland.

Veterinary surgeons in rural practices \vould be well advised to buy the book.

Welche Klimafaktoren sind ffir den Asthmatiker von Wichtigkeit? Von Dr. Viktor Grimm. Berlin: Richard Schoetz, 1928. Pages 284, 8vo. Price, 12 ·60 marks .

The author of this work has done good service in making public what he has been able to learn regarding the etiology of asthma from a study of the existing literature, his own large experience as a physician at the Asthmabad, Reichenhall, Bavaria, and information supplied to him in response to a ques­tionnaire addressed to the members of the medical profession in Holland. Its appearance is opportune in view of the National Campaign against the disease that has recently been initiated in this country. All the known or suspected causes of asthma are dealt with, and special interest attaches to the part that deals with those cases in which the excitant is derived from horses, fowls, and other domesticated animals and records many proved instances.

Das Lymphgefassystem des Pferdes. Von Dr. Herman Baum. Berlin: Julius Springer, 1928. Price, 38 marks.

This work, w'hich has 135 Royal quarto pages of print and 53 illustrations (with the lymph vessels in colour), constitutes a most valuable addition to the literature of Veterinary Anatomy. It does for the lymph vessels of the horse what had previously been done by the same distinguished author for these vessels in the ox and dog. It reflects great credit alike on the author, the artists who collaborated with him, and the publishers.