560 



THE POPULAR SCIENCE MONTHLY. 



be likely to suppose ; and the census returns 

 give surprising accounts of the number of 

 totally deaf persons, it being about 300,000 

 in the United States. There are further 

 those who are somewhat deaf in one ear, 

 those who are obliged to take a forward seat 

 in the church and the public hall, and those 

 who are conscious of a gradual failing of the 

 hearing sense ; also children and adults who 

 receive sounds slowly because they lack 

 quick perception, and persons who fail to 

 distinguish particular shades of sound. 

 With these affections the author couples de- 

 fects of speech, such as stammering, stutter- 

 ing, lisping, mumbling, and mouthing, as 

 mostly originating in some organic fault. 

 The object of her little book is to show that 

 fluent speech may be obtained and under- 

 stood by all who suffer from the different 

 phases of deafness and the different degrees 

 of imperfect utterance. In it she considers 

 the cases of the Deaf Mute and the Stam- 

 merer ; the Very Young Deaf Child ; Signs, 

 Finger-spelling, and Speech ; Teaching the 

 Dumb to Speak ; the Child suddenly Deaf 

 and the Child growing Deaf slowly ; the 

 improvement and development of hearing; 

 How the Hard-of-hearing Adult may enjoy 

 Conversation ; Dull Pupils ; Invented or 

 " Pathological " Language, Lisping, Careless 

 Speech, Stuttering, Stammering, and Cleft 

 Palates. The author has a full understand- 

 ing of her subject, presents it in a clear and 

 earnest way, and urges the need for its more 

 careful consideration by parents, and edu- 

 cators generally. 



BULLKTIN OP THE UnTTKD StATES FiSH COM- 

 MISSION, Vol. XIL for 1892. Marshall 

 McDonald, Commissioner. Washington : 

 Government Printing Office. Pp. 478, 

 with One Hundred and Eighteen Plates. 



The bulletins are issued under a joint 

 resolution of Congress authorizing the pub- 

 lication, from time to time, for distribution 

 in parts and collection in annual volumes 

 not exceeding five hundred pages each, of 

 any matter furnished by the Fish Commis- 

 sion, relative to new observations, dis- 

 coveries, and applications connected with 

 fish culture and the fisheries. The present 

 volume contains a bibliography of the salm- 

 on of Alaska and adjacent regions, and a 

 life history of the salmon, by Tarleton H. 



Bean ; a paper on the viviparous fishes of 

 the Pacific Coast of North America, by C. H. 

 Eigenman ; an account of the fishes of 

 Texas and the Rio Grande Basin, considered 

 chiefly with reference to their geographical 

 distribution, by B. W. Evermann and W. C. 

 Kendall ; a report on the salmon fisheries 

 of Alaska, by Marshall McDonald ; a sum- 

 mary of the fishery investigations of the 

 Albatross, 1882-'92, by Richard Rathbun; 

 a report on the fyke net fisheries of the 

 United States, and Notes on Fishes of the 

 Northern Coast of New Jersey, by H. M. 

 Smith ; an account of the oyster industry of 

 Maryland, by C. H. Stevenson; and two or 

 three papers of more special interest. 



Aerial Navigation. By J. G. W. Fijnje 

 VAN Salverda. Translated from the 

 Dutch by George E. Waring, Jr. New 

 York : D. Appleton & Co. Pp. 209. Price, 



$1.25 



There seems to be good reason for be- 

 lieving that the next great triumph of science 

 will be in the field of aerial navigation. The 

 number and ability of the investigators who 

 are now at work upon this subject, the en- 

 couraging results and the widespread in- 

 terest that their efforts have secured, furnish 

 substantial ground for this belief. After a 

 historical introduction and a discussion of 

 the military importance of aerial navigation, 

 Mr. Fijnje considers the obstacles in the 

 way of navigating balloons, stating the 

 practical results already reached. He then 

 passes to the flight of birds, from the several 

 varieties of which rowing, hovering, and 

 sailing the principles of flying machines 

 proper are derived. Three kinds of ma- 

 chines of the " heavier than air " class are 

 described in a brief chapter. Although 

 MM. Renard and Krebs in 1885 succeeded 

 in driving an elongated balloon at the rate 

 of fourteen miles an hour, the author is con- 

 vinced that balloons must give place to fly- 

 ing machines. Among his conclusions con- 

 cerning the latter are that a flying machine 

 must be supported by a large and strong 

 aeroplane, which must not be utilized to give 

 forward motion. There must be an inde- 

 pendent motor, working continuously, and 

 operating through propelling screws or other 

 device. Some later matter published by the 

 author separately from the foregoing gives 



