1012 



SCIENCE. 



[N. S. Vol. XIV. No. 365. 



almost a necessity. As regards, however, the 

 extension of the system throughout the State, 

 where individual work in the field should be 

 done in order to familiarize the worker with 

 special and local conditions, I fully recognize 

 the incompleteness of the evidence. It deserves 

 to be emphasized, however, that the student of 

 a carefully prepared map has always at hand 

 the accumulated knowledge acquired by the 

 corps of topographers whose painstaking labor 

 it represents — labor which the modern school of 

 physiographers has been quick to use as the 

 basis of their conclusions. It is not assumed 

 that along every trough line of the map lies the 

 course of a fault. In my article it is stated 

 (p. 478) : 



' ' The term ' trough lines ' * * * may, for the 

 present, be given no further signification than 

 lines so favored by nature that the waters of the 

 region have been induced to adopt them for 

 their channels over longer or shorter distances. 

 On a map of this scale the trough lines, if rec- 

 tilinear, should be slightly curved, but inas- 

 much as the present river courses, because of 

 the many accidents of their history, can only 

 roughly approximate to the directions initially 

 given them, it would be an over refinement to 

 introduce a correction of this nature." 



Evidence obtained from the examination of a 

 map by this method can only be of value when 

 cumulative. A single stream which persists in 

 a given direction even for a long distance af- 

 fords little support to the theory, when com- 

 pared with that yielded by a number of smaller 

 streams each approximating to a rectilinear 

 course for a shorter distance, provided the rec- 

 tilinear courses are parallel. A harder layer of 

 rock, or a bai-rier of drift may conduct one 

 stream or the other in its course, but it is in- 

 herently improbable that one of these causes or 

 the other, or both combined, have controlled 

 the parallel river series in an area of such geo- 

 logical structure as we find in the State of Con- 

 necticut. As was pointed out in the paper, it 

 is worthy of note that so few of the master 

 streams of the area follow the slope of the plain 

 of erosion. As regards the larger area of the 

 State the theory may, perhaps, as Professor 

 Davis says, * be regarded as standing in an in- 

 terrogative rather than in a demonstrative at- 



titude,' but it would be doing injustice to the 

 facts to consider the trough lines as isolated 

 lines while ignoring their arrangement in paral- 

 lel series. 



Wm. H. Hobbs. 



physiological effect of diminished air 

 pressure. 

 To THE Editor of Science : The interesting 

 communications of Messrs. Clayton and Ward 

 upon the physiological effects of the diminished 

 air pressure due to mountain climbing recall 

 some records which I made in 1896 during an 

 ascent of El Misti, Peru, similar to that de- 

 scribed by Professor Ward. As the effect of 

 the high altitude upon my condition was in 

 part different from that experienced by him, it 

 may be of interest to describe it. The journey 

 from the observatory at Arequipa, elevation 

 8,050 feet, to the summit of El Misti, elevation 

 19,200 feet, was made on four occasions. The 

 distance is about 25 miles. It is possible to ride 

 on horseback or muleback to the very summit, 

 following a caravan trail across the pampa to 

 the base of the mountain, and ascending by a 

 winding path constructed with great skill by 

 Professor S. I. Bailey when the meteorological 

 station was established. The journey from the 

 observatory to a hut at an elevation of about 

 15,400 feet occupies one day, during which the 

 rider is usually obliged to endure the scorching 

 rays of the sun. The night is passed at the hut, 

 and the final ascent to the summit made on the 

 second morning. This occupies several hours, 

 as the animal stops to rest every fifteen or 

 twenty feet at this altitude. On two occasions 

 I was obliged to walk a short distance to cross 

 snow which had drifted across the path, and 

 realized the extreme diflBculty of breathing 

 during the exertion required. The return from 

 the summit to the observatory is easily made on 

 the second day, but on two occasions I spent a 

 second night at the hut. 



The effect of the altitude upon me was chiefly 

 to cause headache, sleeplessness and partial loss 

 of appetite. On one occasion while at the sum- 

 mit I experienced a decided feeling of faintness 

 for a short time. During the nights at the hut 

 the temperature was about 32° Fahr., but it 

 seemed impossible to keep the body warm, in 



