S. L. Penfield—A patites containing Manganese. 369 
No, 2, by Mr. F. P. Dewey. 
n. 
Zz I. ea Ratio 
P.O; 40°94 40°99 40°96 288 1 
Al,O; 52 “AY ‘50 
Pods a 08 08 
a AT9 AT-95 AT-87 855). ; 
MnO 250 2-47 2-48 035 t Pe San 
Ca 4 101 "35 
3°84 3°84 3°84 “202 “10 
Insoluble 06 “05 06 "000 
99°83 
No. 3. Specific gravity, 3144. 
IL I. ean. Ratio. 
P.O; 41°47 AL‘4T 41-47 292 1 
Na +29 ai s 
a 49°10 49°13 49°12 B77), 3 
MnO 1-98 1-94 1:96 t ge We schsas 
Mg 2-88 072 25 
2°68 2°68 141), : 
Cl 10 10 4 144 49 
Insoluble 1°50 1°50 
pene it: * 
99°93 
No, 4. Specifie gravity, 3°22 
hy IL. Mean. Ratio. 
P.O, 39°58 39°59 39°59 279 1 
Al,O; 56 56 56 
ae! en “17 wes 
a 46°52 46-76 46°64 833). . 
0 1°38 1.31 1°35 eet oh ae 
ZnO “03 03 03 
Ca 3°57 089 "32 
3°40 3°34 3°37 177 
“04 “178 “64 
CaCO, 2°82 2°82 001 
52 
99:26 
The above ratios coincide very nearly with that required by 
the accepted formula of the species, viz: 1:3: 0°33 : 0°67. 
These analyses are the first that show the presence of notable 
quantities of manganese replacing calcium in apatites. It is 
also to be noted that these apatites are essentially fluor-apatites 
containing only a trace of chlorine. 
n closing, I wish to express my thanks to Professor George 
J. Brush, who has kindly provided me with the material for 
Carrying on this investigation, and to Mr. Frederick P. Dewey, 
whose analysis I have quoted. 
