400 On the Chemical Composition of Phosphatic Minerals 
Spain and Portugal, in the course of the year, send us a good 
many cargoes of phosphate. 
From Norway we receive from time to time a comparatively 
small amount of apatite ; and larger quantities of a crystallised 
or hard variety of apatite are sent to us from Canada, under the 
name of American or Canadian apatite. 
Another phosphatic mineral largely imported into England 
at the present time is Charleston, or South Carolina, land and 
river phosphate. 
From St. Domingo we obtain Alta Vela phosphate ; and from 
the Redonda Island a crude phosphate of alumina which bears 
its name. 
Other phosphatic minerals, sometimes called rock-guano, are 
found in more or less considerable quantities in the small coral- 
islands of Sombrero, Navassa, St. Martin's, Petro Keys, Aruba^ 
and some other uninhabited small islands in the Caribbean 
Sea. All these, and some other phosphatic minerals, have 
been, and still are, constantly referred to me for examina- 
tion. Probably nobody has had so man}^ opportunities as I 
have of becoming acquainted with, or of obtaining a large ex- 
perience in, all kinds of phosphatic minerals which are actually 
utilised in the manufacture of superphosphates, and similar arti- 
ficial manures, which are produced in hundreds of thousands of 
tons annually in the numerous manure works all over England. 
As a sequel to my paper published in the pages of this. 
Journal in 1861, I propose to give a brief account of a num- 
ber of phosphatic minerals which, at the time of the publication 
of my former paper, either had not been discovered, or were of 
interest only to scientific men. 
Whilst treating of the composition of some of the more 
recently discovered phosphatic minerals, and their value for 
agricultural purposes, it may not be amiss for me to refer to 
some of the minerals, analyses of which were given in my 
former paper. A few selected analyses, made by fne during 
the last and preceding years, it is hoped may be found useful 
in showing the chemical character of the present supplies 
of coprolites, of Sombrero, Spanish, and one or two other 
phosphates. 
1. French Coprolites. 
Most of the phosphatic nodules which are known in England 
under the name of French coprolites are dug up in the neigh- 
bourhood of Boulogne. They are generally sold as Boulogne 
coprolites, and are hardly distinguishable from some of those of 
inferior quality in Norfolk and Ijcdfordshire. Boulogne copro- 
