POPULAR MISCELLANY. 



427 



duction by either of these ships on her next 

 trip. Nearly equal speed has been made be- 

 tween England and Australia. At the be- 

 ginning of the century this passage required 

 eight months by sailing-vessels, and is now 

 made by steamers in about six weeks. The 

 Ormuz, launched in ISSV, was designed to 

 greatly reduce this time, and, although at 

 first not reahzing expectations, in October of 

 the same year she exceeded them by cover- 

 ing the distance between London and Ade- 

 laide m a trifle under twenty-four days. 



Colors of Flying-Sqnkrels.— A paper 

 was read in the American Association, by 

 Mr. W. E. Taylor, on color variations of Ne- 

 braska flying- squirrels. The American fly- 

 ing-squirrel presents a range of geographi- 

 cal variation in size quite unparalleled in 

 other members of the Sciuridce. On the 

 other hand, the coloration is remarkably con- 

 stant. The local variations in color were 

 illustrated by descriptions and comparisons 

 of five specimens examined by the writer, 

 all collected near the Missouri River, in Ne- 

 braska, at different times and places. The 

 writer concludes : 1. That the measurements 

 correspond to the Northern variety, while 

 the colors correspond more nearly with the 

 Southern varieties. 2. Local variations in 

 color are great, these variations existing in 

 members of the same nest. 3. Locally, at 

 least, the two varieties appear to grade into 

 each other. 4. The degree of coloration on 

 some parts of different specimens does not 

 vary in the same rate. 



Value of Experimental Psychology. — 



Pointing out the advantages of the experi- 

 mental method of psychological investiga- 

 tion, combined with the introspective, Dr. J. 

 McK. Cattell, of the University of Pennsyl- 

 vania, says: "Experiment is not meant to 

 take the place of introspection, but is meant 

 to make scientific introspection possible. 

 The study of consciousness is, as we all 

 know, fraught with peculiar difficulties. It 

 is not easy to be at once the observer and 

 the observed. The eye sees not itself, and 

 the phenomena are both complex and tran- 

 sient. The best results have been obtained 

 when introspection has been combined with 

 the study of the objective manifestations of 

 the contents of other minds, more especially 



when these have on the one hand become 

 fossilized, as in language, customs, art, etc., 

 or, on the other hand, are relatively simple, 

 as in children, in savages, and in disease; 

 but, under circumstances the most favorable 

 to scientific observation, there are serious 

 difficulties in the way of exact observation 

 and measurement, and it will be found in 

 psychology, as elsewhere in science, that ex- 

 periment gives the most trustworthy and accu- 

 rate results. Experiment calls up the phe- 

 nomena to be studied when wanted, and by 

 keeping certain conditions constant and by 

 altering others gives the best chance for anal- 

 ysis ; above all, it enables us to photograph 

 the transient phenomena and subject them 

 to objective examination and measurement." 



Continental Centers. — The orographic 

 centers of the several continents have been 

 graphically determined by M. A. de Tillo as 

 follows : 



These four centers form a fairly regular 

 quadrilateral. The longest side (92°) is the 

 one between the Asiatic and North American 

 centers. The African center is distant 82° 

 from the South American center. It is 

 worthy of remark that the distance between 

 the centers of the double continents is ap- 

 proximately the same, the center of Asia be- 

 ing 70° from that of Africa, while the cen- 

 ters of the double American continent are 

 separated by 73°. The geometric center of 

 the four continents is in the region of the 

 Azores and the Canaries. 



The Energy in an Earthquake.— After 



explaining, in the American Association, the 

 impossibility of calculating the intensity of 

 an earthquake more than approximately, 

 Prof. T. C. Mendenhall applied a formula to 

 determine the energy involved in the Japa- 

 nese earthquake of January 15, 1887, which 

 disturbed over 30,000 square miles of terri- 

 tory. He said: "Assuming a mass of 150 

 pounds per cubic feet, and taking a cubic 

 mile as the volume to be considered, I find 

 that to put it in vibration required the 



