the sand is compact and hard. Thus the sand roads and the clayed roads supplement each other. The road-making clays are of a red or yellowish color, indicating a high percentage of iron compounds which probably assist in the bonding power of the material. In texture the clay is rather coarse, and breaks up readily. BOG IRON ORE. Bog iron ore occurs in various parts of the State, but usually in thin deposits and of local extent. It has been stated by Shaler, (U. S. Geological Survey, 15th Ann. Rept., p. 272, 1895), that where the surface of a limestone road can be covered with iron ore, the firmness of the mass is much increased. An iron oxide, such as bog iron ore, serves as a cementing material, and this is doubtless the explanation of its usefulness for this purpose. PHOSPHATIC ROCK. Phosphate of a too low grade or too high in objectionable impurities to work commercially may serve in some localities as a useful road rock. The hard rock phosphate is harder than limestone and is reported to have better cementing qualities. GEOLOGICAL INVESTIGATIONS IN FLORIDA PREVIOUS TO THE ORGANIZATION OF THE PRESENT GEOLOGICAL SURVEY. The record of the geological investigations in Florida as contained in the literature, is briefly summarized in the following pages. It has been found impossible to mention all of the important papers, and only those which are especially necessary to an understanding of the course of development of the geological researches in this State are included. In the bibliography at the end of the chapter will be listed all the titles that have been found relating to the geology of Florida. This summary is given in the beginning of the State Survey's work in order to take stock, as it were, of the results already arrived at in this field. The numbers given in parenthesis in the text refer to the bibliography. A number of references to Florida Geology occur in publications issued previous to the acquisition of the territory of Florida by the United States in 1821. M. Catesby as early as 1771, wrote on the natural history of Carolina, Florida and the Bahama Islands (24), and in 1791, William Bartram published the first edition of his travels through North and South Carolina, Georgia and east and west Florida (15). Bartram's account is of interest as being one of the early publications based upon direct observations. William McClure's memoir, "Observation on the Geology of the United States," includes mention of Florida along with the other coastal plains States. The first edition of this work appeared in 1809 in the Transaction of the American Philosophical Society (141). A second edition revised and enlarged was published in book form in 1817, and in the "Transactions" for 1818. The science of Geology at this early date was very imperfectly developed as may be inferred from the fact that McClure accepts the Wernerian classification. Florida was believed to belong entirely to the formation known as the Alluvium, the fourth division in the Wernerian system. A paper by John Finch entitled "Geological Essay on the Tertiary Formations in America," published in the American Journal of Science for November, 1823 (69), is credited by Professor William B. Clarke (25) as the first attempt to correlate the deposits of the coastal plains on scientific grounds. This paper refutes the prevalent idea that the coastal plains consist entirely of alluvium. With regard to this point, Finch states, page 32, that: "In America, an immense tract of country, extending from Long Island to the sea of Mexico, and from thirty to two hundred miles in width, is called an alluvial formation, by most of the geologists who have written upon the subject, and by some it appears to be considered as an exception to the general arrangement and position of strata, which are found to occur in other countries. "From an examination of fossils brought from that quarter of the United States, from a personal inspection of some of the strata, and the perusal of most of the publications which bear a reference to it, I wish to suggest that what is termed the alluvial formation, in the geological maps of Messrs. Maclure and Cleaveland, is identical and contemporaneous with the newer secondary, and tertiary formations of France, England, Spain, Germany, Italy, Hungary, Poland, Iceland, Egypt and Hindoostan' Specimens of Florida clays from Escambia Bay, seven miles above Pensacola, contained in the Academy of Natural Science of Philadelphia are mentioned, (p. 37.) A paper published the following year, 1824, by R. Dietz, contains a description of the coquina rock of Anastasia Island at St. Augustine (63). In a note appended to this paper Thomas Say identifies and lists the shells contained in a mass of the coquina rock. The territory of Florida, "A recent and valuable acquisition to the United States", is described by James Pierce in a paper published in 1825 (158). This paper, like Bartram's, is based upon actual explorations. Central Florida was visited by Pierce and the topographic features accu rately described, including the limestone rock, sinks, natural wells, subterranean streams, "savannas" or "prairies," lakes and hammock lands. A great savanna, believed to be one hundred miles in circumference, located in south Florida (presumably the Everglades), is reported (p. 124) as having been seen by Colonel Gadsden. The existence of a large permanent lake located by maps in the southern part of the peninsula (evidently referring to Lake Okeechobee) is doubted. A paper by Charles Upham Shepard, published in 1833 (182) is of interest chiefly from the quotations which are incorporated from Bartram and others, describing the springs of Florida. In referring to Manatee Spring and to a sink described by Bartram as "near Tallahassee," this writer evidently confuses the present city of Tallahassee with the ancient Indian village of Tallahasochte, which was located on the Suwannee River. A paper published in 1838 by Henry Whiting (205) contains an interesting description of Florida, including some observations of geologic interest. The coraline formations of the keys is noted, the shell formation of the upper St. Johns River is mentioned, and the coquina rock at St. Augustine described. It is interesting to note that at this date both the Everglades and Lake Okeechobee are referred to in doubtful terms. The next group of papers of importance appeared in 1846. One of these, by John H. Allen (11), entitled "Some Facts Respecting the Geology of Tampa Bay," gives an accurate description of the limestone along the Hillsboro River, together with a partial list of fossil shells contained in the limestone. Allen falls into the error of regarding the limestone at Tampa Bay as identical with the limestone of the interior, including that observed by him in central Florida, and that reported to occur in the Everglades. T. A. Conrad accompanied an expedition sent out by the Navy Department during the winter of 1842 under the command of Capt. Powell. The expedition visited the |