portunities for travel, lie was impressed with the importance of interesting legislatures in geological surveys, and he took measures to enlist the government of Massachusetts in such work. With this aim in mind he published a lengthy review of Olmsted's survey of North Carolina in the American Journal of Science, in 1828. Near the close he says: "We wish now to ask the intelligent legislator whether such a development of internal resources as this report exhibits does not amply remunerate the State of North Carolina for the comparatively trifling expense of this survey; and whether so great success. . . does not strongly recommend that this example be followed by other States of the Union."
As the result of this and other efforts, the State of Massachusetts commissioned him to make a geological survey of her territory in 1830. Three years were spent in the explorations, and the work was of such a high character that other States were induced to follow the example of Massachusetts, and similar surveys were organized in Tennessee, Maryland, New Jersey, New York, Virginia, Maine, Rhode Island, New Hampshire, Connecticut, Pennsylvania, Ohio, Delaware, Michigan, Indiana, Kentucky, and Georgia. The State of New York sought his advice in the organization of a survey, and followed his suggestions, particularly in the division of the territory into four parts, and appointed him as the geologist of the first district. He entered upon the work, but after a few days of labor he found that he must necessarily be separated from his family, much to his disinclination. He also conceived the idea of urging a more thorough survey of his own State; hence he resigned his commission and returned home. The effort for a resurvey of Massachusetts was successful, and he was recommissioned to do the work. The results appeared in 1841 and 1844—the first a quarto report and the last the geological coloration of a map based upon Borden's Trigonometrical Survey.
Independently of the survey came the discovery of fossil footmarks. As far back as 1800 Pliny Moody had observed trifid markings upon sandstone which he called the tracks of birds. In 1835 Mr. W. W. Draper, of Greenfield, Mass., noticed similar impressions, and drew the same conclusions. Mr. Draper remarked upon them to Dexter Marsh and Colonel William Wilson, who in turn consulted Dr. James Deane, who wrote to Professors Silliman and Hitchcock. All agreed to refer the investigation to Prof. Hitchcock, who propounded the fundamental principles of ichnology in the January number of the American Journal of Sciences for 1836. The announcement was not favorably received by many geologists, while the general public gave expression to their views by the employment of ridicule. The subject was re-
