1895.] Fluorine as a Test for the Fossilization of Animal Bones. 453 
Ameins, of the Rhine at Strasbourg, and of the mineral waters 
of Plombiéres, Contrexville, Antogast, Chatenois, Vichy 
(Compte Rendus, 1857, Vol. I, page 783; Vol. II, pages 250 and 
331). Also by Charles Méne in the waters of the Rhone, 
Saone, Loire; by Rose in the well-waters of the neighbor- 
hood of Berlin (Compte Rendus, 1860, Vol. I, page 731); in 
the waters of Plombiéres by Jutier and Lefort (9 or 10 mille- 
grams per litre); Carlsbad by Berzelius (3 mg, 2); Kreus- 
brunnen by Berzelius (traces) ; Kissingen and Aix-la-Chapelle 
by Leibig (traces); d’Orezza by Poggiale, the latter ones cited 
in the Dictionaire de Chimie by Wurtz, Vol. II, page 1206. 
Clemm and Forchhammer recognized in the deposits formed 
by the evaporation of sea water, phosphate of lime accom- 
panied by carbonate and fluoride (Daubrée, Gisements de 
chaux phosphatée, Annales de Mines, 1868, page 81.) 
The existence of fluorides has been also discovered in 
different substances, both animal and vegetable, as blood, 
milk, urine, yellow of the egg (Nicklés, Compte Rendus, 1857, 
Vol. II, page 331; Tamman, Zeitschrift f. physiolog. Chimie, 
1888, page 322). 
And finally, this substance is much more extensively dif- 
fused than has been generally believed. There is, therefore, 
nothing astonishing that the infiltrated waters which come 
in contact with animal bones should contain in small quan- 
tities the fluorides in solution, and should produce, in the 
course of a long period of time, a sensible modification in 
the composition of those bones; but which must have been 
affected with extreme slowness because of the very feeble pro- 
portion of fluorides in solution. Ordinarily the traces are so 
minute that it is extremely difficult to recognize them by an- 
alysis, and it must have taken a great number of centuries for 
the variation in the proportion of fluorine to become appreci- 
able. The other changes in the nature of bones are often 
much more rapid and more irregular. An augmentation of 
several hundredths in the proportion of oxide of iron can be 
produced in a short interval of time. It isthe same with a 
notable variation in the proportions of phosphate and carbon- 
ate of lime; while, as for the silica, sulphate of lime, pyrites 
