162 ROYAL SOCIETY OF CANADA 



For three or four days before observations were begun, there had 

 been a good deal of rain. The stakes were set at 3 p.m. Saturday, and 

 the level of the water at that time would of course be exi^ressed by tha 

 straight horizontal line AB. Later in the day there were showers, and 

 Sunday was cloudy. There was a rize above zero of line I. at 4, but a 

 marked fall in the other pits, no doubt all due chiefly to a settling of the 

 water towards the margin. At 6 p.m., after a clear day, II., there was a fall 

 in all of the pits, but this was least in 4 and greatest in (3 and 11. Dur- 

 ing the night, III., there was further sinking, but much less than during^ 

 the day, showing that the drop is largely due to evaporation, and not 

 simply to draining away. But in pit 4 during the night the water rose 

 a little, showing that the water in the bog settled out towards the edge 

 more than evaporation there could compensate. Lines IV. and V. give 

 the same result. Unfortunately, no observation could be made Wednes- 

 day evening. Thursday night it rained heavil}', thus raising the level in 

 all of the pits ; and to prevent confusing the diagram for the earlier 

 days, 1 have made a separate one for the remaining observations. Thus, 

 line VIII. shows a general rise above VII. in all of the pits, even rising 

 above zero at 4, but the pit 2 does not rise in the same proportion as the 

 others, showing that the water had not j'et settled appreciably towards 

 the extreme edge of the bog. There was more rain dui'ing the day, of 

 which the ettects are seen in line IX., which rises above all others, and 

 the rise at 3 and 2 shows a settling towards the edge of the bog. There 

 was little or no rain in the night, as shown by X., whose great rise at 2 

 shows a marked settling towards the edge of the bog. Saturday was 

 fine, and there was a further drop in all of the pits, as shown by XL 



It is plain that while on the high part of the bog the ftill in general 

 is greater the higher the part, there are some exceptions. Thus, the 

 drop in 6 is greater than 7, and greater in 11 than in 12. I think, but 

 am not sure, that 6 and 11 are in somewhat drier parts of the bog than 

 are the others. Since the fall is more rapid b}' day than by night, it 

 must be due largely to evaporation. But since evaporation must be- 

 nearly even over all the sui'face, the lesser drop near the edge must indi- 

 cate a slow settling in that direction. The conclusion, then, seems justi- 

 fied that the hydrostatic water of these bogs is derived from rain-fall ; 

 that after a rain it not only evaporates, but settles slowly towards the 

 margin. But why it stands at such a hciglit. and does not break through 

 the lower margin, I do not understand, it is purely a question of 

 physics, why it settles so slowly. It is to be remembered that actually 

 the pits are at successively lower levels from 12 (or at least 11) to 2, 

 which makes the slowness of the settling all the more remarkable. The 

 study of the physics of these bogs would yield good results to a coni- 

 petent student. 



