to calculate the amount of recession. By correspondence and otherwise we have endeavored to collate all of this information, and it is recorded in these maps. The first systematic marking was done in 1888 by the Rev. W. S. Green. He daubed with tar a number of boulders adjacent to the ice, and its limitations that year may be easily made out by following these marked rocks. Our own work has also included the marking of the edge of the ice as it was in 1887 upon a large boulder beside the trail, just as one emerges from the alder bushes. A photograph taken at that time by us, and showing this huge rock imbedded in the ice, gave the basis for the mark. We have also marked several rocks in the bed moraine, and from one of these having on it a circle and cross the measurements have been made since 1900.
The following table gives the results of the observations for recession:
Illecillewaet Glacier, Recession of Tongue of Ice from Rock C.
| Date of Observation. | Distance Tongue of Ice to Rock C. |
Recession of Ice since previous year. |
| Aug, 17, 1898 | 60 feet | |
| July 29, 1899 | 76 feet„ | 16 feet |
| Aug. 6, 1900 | 140 feet„ | 64 feet„ |
| Aug. 5, 1901 | 155 feet„ | 15 feet„ |
| Aug. 26, 1902 | 203 feet„ | 48 feet„ |
| Aug. 25, 1903 | 235 feet„ | 32 feet„ |
| Aug. 14, 1904 | 240½ feet„ | 5½ feet„ |
| July 25, 1905 | 243 feet„ | 2½ feet„ |
| July 24, 1906 | 327 feet„ | 84 feet„ |
(d) The most detailed and probably the most interesting work we have done, however, is the measurement of the rate of flow. Rev. W. S. Green made some observations, but, as he was not equipped with
