1 88 FLORIDA GEOLOGICAL SURVEY I3TH ANNUAL REPORT 



is fairly typical of what is here called semi-calcareous hammock 

 land, and the, third and fourth of sandy hammocks. 



Bulletin 43 of the Florida Agricultural Experiment Station, by 

 A. A. Persons (1897), contains many analyses of central Florida 

 soils, made by J. P. Davies. by essentially the method recommended 

 by the Association of Official Agricultural Chemists in 1895. 

 These have been made the basis of several published statements 

 about the average composition of Florida soils,* and at first glance 

 they appear to be valuable sources of information; but closer scru- 

 tiny shakes one's faith in them. The samples were collected by sev- 

 eral different persons, apparently mostly without previous experi- 

 ence or expert supervision, and some of them are not described suf- 

 ficiently to make it clear just what type of soil they represent. Al- 

 though the analyses cover almost every constituent that is commonly 

 considered in such w^ork, except manganese, and are carried out to 

 four decimal places, they contain so many inconsistencies as to sug- 

 gest either careless work or typographical erors, or both. (Prof. 

 Persons a few years before his death informed the writer that he 

 was unavoidably absent from the State for several weeks while this 

 bulletin was going through the press, which may account for some 

 of the errors.) In many cases the analyses show more humus or 

 less potash, iron or alumina in the subsoil than in the soil, which 

 is strange if true, and much less potash and lime than is given in 

 analyses of somewhat similar soils in other publications. As there 

 is no analysis from central Florida in the bulletin that is free from 

 one or more of these defects, it has been thought best not to use any 

 of them. 



In Whitney's Bulletin 13, previously mentioned, the averages 

 of partial analyses of four to ten samples of several types of soil 

 are given. The method of analysis is not stated (and could not 

 be recalled by Prof. Whitney 17 yeafs later), but the results seem 

 consistent with those obtained by the A. O. A. C. method (which 

 reveals considerably less potash than Hilgard's acid digestion 

 method). The same bulletin also gives for several types of soil 

 the total amounts of soluble salts in the soil solution, a factor of 

 considerable significance. The results are set forth in Tables 16 

 and 17. In the former, D represents "Etonia scrub" and E high 



*Some of them have been quoted in our 4th Annual Report, pp. 65-71. 



