all important points on the way. Instruction by lectures and examinations was given in mineralogy, geology, botany, zoölogy, chemistry, experimental philosophy, and practical mathematics, particularly land surveying, harbor-surveying, and engineering. One of the largest boats in the flotilla was fitted up as a laboratory, with cabinets in mineralogy and geology, and also scientific books for reference. Students were taught the method of procuring specimens, and were required to make collections of whatever was interesting on the route.
The public mind was finally awakened to the importance of the work which these explorers and investigators had carried on single handed. Government now came to the aid of science. In 1824 one State Legislature, that of North Carolina, authorized a geological survey to be made. This example was followed in 1830 by Massachusetts, and soon after by New York, Pennsylvania, Virginia, and other States, and also by the national Government, until, as is now well known, the whole territory of the United States and Canada either has been or is in the process of being surveyed. Several of the State surveys published independent volumes on the mineralogy of their respective States, and these surveys have been a powerful auxiliary in extending our knowledge of the occurrence of minerals on this continent. The opening of mines and quarries throughout the country has also furnished abundant material for study. The large number of original contributions which have been published in the volumes of State surveys, the treatises by American authors, and the still larger number of memoirs and papers communicated to our academies of science and scientific journals, can not be even enumerated in this place; neither is it my purpose to attempt to give here a list of the names of those who have been actively engaged in making researches on American minerals. Still less can I attempt to give an account of the work that has been and is being done by living mineralogists. The sketch which I have presented of the four typical workers has in a measure shown the character of our early mineralogists, the earnest spirit in which they labored, and what they accomplished in the first quarter of the century. The point to which the science has reached in the last quarter of the century can not be unfamiliar to you all.
In the time that remains I desire to call your attention to some of the developments made in the field in which our mineralogists have worked. It was thought by many scientists in the first half of this century that our rocks seemed likely to afford less variety of mineral contents than the rocks of Europe. Further study, however, and more careful and extended observations, encourage us to believe that our mineral riches, even in variety of species, will compare favorably with those of other continents. Already fully one half of the known mineral species have been found here. The present number of known minerals is variously estimated to be from seven hundred to one thousand. There have been described, as occurring here, nearly three hun-
