182 EXPERIMENT STATION EECOED. [Vol.36 



A positive test was never obtained in the absence of a positive von Pirquet 

 reaction. A large percentage of clinically normal individuals giving positive 

 von Pirquet reactions, however, yielded negative fixation tests. 



It is deemed that " the practical absence of a reaction in nontuberculous cases 

 makes this test, when positive, of far greater value in the diagnosis of tubercu- 

 losis than any of the biologic tests for tuberculosis thus far discovered." 



Studies in immunization against tuberculosis, K. and S. Von Ruck (Nciv 

 York: Paul B. Hoehcr, 1916, pp. Xr/+^.39).— This volume is divided into thre- 

 general parts : Theoretical considerations ; practical immunization against 

 tuberculosis ; and experimental studies in the immunization against tubercu- 

 losis. Clinical and experimental data collected by the authors in their study 

 covering a number of years are included. 



Tuberculosis in Normandy, Fr^ger (Bui. Soc. Cent. MM. ViL, 92 (1916), No. 

 8, pp. 123-132). — The prevalence and means of suppression of the disease are 

 briefly discussed. The value of sanitary housing and stabling as prophylactic 

 measures is strongly emphasized. 



Sheep diseases, E. T. Baker {Chicago: Amcr. Jour. Vet. Med., 1916, pp. 237. 

 2)ls. 6, figs. 66). — Following discussions of the history of the breeds (pp. 15-52). 

 the anatomy of the sheep (pp. 53-C2), hygiene (pp. 63-74), and medicines and 

 tlieir administration (pn. 75-83), the more important diseases, poisonous plants, 

 predatory enemies, etc.. of sheep are briefly dealt v/ith. 



Shoeing and balancing' the lig'ht harness horse, J. Claimc {Buffalo, N. Y.: 

 The Horse World Co., 1916, pp. 101. pi. 1, figs. 50).— A small handbook. 



The epidemiology of pectoral influenza of the horse, K. Macek C'Viener 

 Tierdrztl. Monatssclir., 2 (1915), Ao. 12, pp. 553-567; ahs. in Jour. Amer. Yet. 

 Med. Assoc., 49 (1916), No. 6, pp. SJ/S, 8.'f9).— The autlior first refers to the work 

 of Gaffky and Liihrs, previously noted (E. S. R., 31, p. 382), and then i*eports 

 studies made of 76 of 380 horses in a large stable that were affected with pec- 

 toral influenza (Brustseuche). His investigations led to the following conclu- 

 sions : 



" The incubation stage of pectoral influenza is mucli longer than has been 

 generally supposed. In working horses it is from three to four weeks, while in 

 resting horses twice this period may elapse before the outbreak of visible signs 

 of the disease. Tliis may account for outbreaks caused by bringing horses, 

 quarantined for four weeks, into contact with healthy horses. Generally, during 

 a four weeks' quarantine, tlie disease will make itself manifest. An infected 

 liorse can infect another horse not alone when distinct clinical symptoms of in- 

 fluenza are present, but also in the incubation stage, while it still appears to be 

 in good health, and especially in the last few days preceding the outbreak of 

 the disease. 



" The spread of influenza may be checked with certainty if the first cases are 

 recognized and promptly isolated, thus preventing contact between infected and 

 noninfected horses. The isolation stall need not be far from the others and 

 may even be among them so long as healthy animals are not exposed by con- 

 tact. The direct transmission of influenza from horse to horse is the principal 

 way in which it spreads. In this connection the stall, as well as various inter- 

 mediate carriers (i. e., attendants, dirt, straw, feed, rats, mice, sparrows, 

 blankets, harness, pails, etc.), play an unimportant role. Apparently the 

 causative agent of influenza soon dies outside of the body of the horse. 



" The spread of influenza from place to place is to be explained according to 

 the previously made observations, i. e., tliat horses having a long incubation 

 period transmitted the infection to other horses with which they had come in 

 contact. 



