*THE POPULAR SCIENCE MONTHLY.*

The first striking thing to be observed in Table III. is the fact that the average age is a few months higher than the median throughout in the totals of all colleges. In the past fifty years, the average age of graduation has remained quite unchanged, while in the past forty years, the average has fallen one and a half months. This difference

is, however, probably too small to be in itself significant, so that we may conclude that there is neither any actual change in the average, nor any definite tendency observable towards rising or falling.

In the above discussion of averages, each college has been given the same weight as every other. Now, we may look. at the same matter from another point of view. We may bunch all the graduates, as though

they were all students of one great college; and, still assuming that they will be about equally distributed through the months of any given year — an assumption which by the now very much larger numbers is made doubly secure — we may take the average for the five decades since 1850. By this method we obtain the following results:

1850-59. | 1860-69. | 1870-79. | 1880-89. | 1890-99. | 1900- . | |

Yr. M. | Yr. M. | Yr. M. | Yr. M. | Yr. M. | Yr. M. | |

Av. | 23 3.0 | 23 5.4 | 23 4.8 | 23 3.9 | 23 6.1 | 3 0.5 |

Even here, where every concession possible is allowed to the weighting of the averages by the few colleges which in the last decade have relatively much larger numbers, together with their consistently