332* 



faces, of repelling-, attracting, selecting; hence inferring, that in 

 the surface of the arteries, there did not prevail that attraction 

 which caused the capillary phenomena in dead tubes. 



Proceeding to illustrate his position by the phenomena exhi- 

 bited by the microscope, and by the occurrences familiar to the 

 surgeon during operation, he concluded that the inner surface of 

 the bloodvessels had an influence on the blood contained, of pre- 

 serving it fluid, and of resisting attraction : But that, when the 

 vitality of their coats was diminished or disturbed, as by the vio- 

 lent tearing of the artery ; then coag-ulation of the blood, and at- 

 traction of the blood to the sides of the artery, took place, by which 

 the hremorrage was stopped. 



2. On a Peculiar Structure observed by the Author in the 

 Ice of Glaciers. By Professor Forbes. 



This structure, which appears to have escaped the notice of 

 authors on the subject, is a veined or ribboned appearance which 

 pervades the whole ice of many glaciers. The veins or bands are 

 occasioned by the alternation of ice more or less compact ; that 

 which is porous approaching to white or whitish green, the denser 

 ice having a bluish tint. The thickness varies from a fraction of 

 an inch to several inches, and the parallelism may be considered 

 as complete through considerable spaces. It extends in more or 

 less complete development from the neve, or uncompacted glacier, 

 down to the inferior termination ; and during the greater part of 

 this space, in the case of the lower glacier of the Aar, the bands 

 were parallel to the lofty walls by which the glacier was bounded 

 laterally ; their position was generally vertical, but sloping from 

 below upwards and outwards as the distance from the sides of the 

 glacier diminished. Towards the lower end of the glacier the 

 structure became very obscure, and for a time nearly vanished. 

 It appears, however, that these bands or veins change their direc- 

 tion from longitudinal to transverse, their outcropping being pa- 

 rallel to the end of the glacier, the apparent strata there dipping 

 inwards at an angle of 10" or 20^. It is this appearance which 

 has given rise to the mistaken idea of horizontal stratification in 

 glaciers. The veined structure rises towards the sides or sup- 

 porting walls, and has altogether the appearance of being deter- 

 mined by the contour of the ice, and perhaps by the lines of 

 greatest pressure in its interior. In the case of the lower part of 

 the glacier of the Rhone, the veined structure forms conical sur- 



