196 PROCEEDINGS OF THE ACADEMY OP [1883. 



If this be incontrovertible, it opens up an interesting question 

 as to the cause of the desiccation in the vicinity of the big trees. 

 The ratio of disintegration in a mountain peak, b}' the frost, rains,- 

 and elements generally, and the descent of the loose mass to the 

 lower lands by the simple law of gravity alone, would depend on 

 the width of the peak, as well as the nature of the material. In 

 the process of ages, peaks covered with snow would be lowered 

 till they were no longer snow-capped in summer, and thus lower 

 regions in the vicinit}^, covered perchance with Sequoia, would be 

 under dryer atmospheric conditions. To a greater or less extent 

 this must be the case in all mountain changes, but whether this 

 could have been going on to any appreciable extent in the few 

 thousand years during which these trees have occupied the spot, 

 is a question for geologists to determine. However, Mr. Muir 

 himself gives good reasons for the belief that these trees followed 

 from the west, eastwardly, in the close wake of retreating glaciers, 

 and when the atmospheric moisture, as well as that of the earth 

 contiguous, must have been more moist than now. 



In regard to the age of the trees, Mr. Meehan said doubts had 

 been expressed whether the Sequoia might not make more than 

 one annual circle of wood a j'ear, and thus render the count by 

 these annual circles unsafe. He had given close attention to this 

 point on the ground, by measuring the height of thrifty young 

 trees, and estimating by the growth per year the probable age. 

 A tree of say thirt}', forty or fifty feet, would be seen to be about 

 that many years old. The diameter of the trunk would then be 

 taken and found to correspond with the one annual ring per year 

 in the sections of the larger trees, as per actual count. There 

 would be no question but the larger trees were over 2000 years old. 



He found that when about three or four hundred years old, the 

 trees ceased to increase in height to any appreciable degree, the 

 effort of the tree being more in a lateral direction, and the nutri- 

 tient matter necessary to the building up of the trunk was mainly 

 the work of the side branches. Tiie height of one called " Haver- 

 ford," after our sister college, he found, by a rough triangulation, 

 to be about 249 feet. 



September 25. 

 Rev. Dr. H. C. McCook, Vice-President, in the chair. 



Thirty-seven persons present. 



The death of Alexis T. Cope, a member, was announced. 



Restoration of Limbs in Tarantula. — Rev. Dr. McCooic re- 

 marked that the tarantula exhibited had been kept in confinement 

 nearly a year, fed during winter on raw beef and in summer on 

 grasshoppers. In the spring it cast its skin, by a laborious 



