ELISHA MITCHELL SCIENTIFIC SOCIETY. 69 
constant, 1:1, while the silica and water vary between 
certain limits. He has assumed as these two limits: 
RAI,Si,O,,+6H,O and 
R, Al,Si,O,,+6H,O 
The first would be a hydrated calcium albite and the 
last a hydrated anorthite. From a comparison of the 
wellsite-stilbite series, 1t seems more probable that the 
anorthite end would be RAI,Si,O,+2H.0, or doubling this 
for better comparison with the formula of Fresenius, 
R,A1LS1,0,,+4H,0O. 
It is not unreasonable to expect that the first or anor- 
thite member of this series may be found in nature and 
the completed series would then be: 
Anorthite limit... RAI,Si,0O,+2H,O (not yet identified) 
Wellsite.........RAI,Si,0,,+3H,O 
Paulipsite .......- RAIS1,0,,+43H,0 (perhaps 4H,0) 
Harmotome ......RAI,Si,O,,-+5H,O 
Siilbite ....++....-RAI,Si,O,,+6H,O 
It is also interesting to note that the formula of the 
new mineral wellsite is the same as that assigned to 
edingtonite, but the latter is essentially a barium mineral 
and being tetragonal shows no crystallographic relations 
to wellsite. 
Pyrognostlics.—When heated vefore the blowpipe, the 
mineral exfoliates slightly and fuses at 2°5-3 to a white 
bead, coloring the flame slightly yellow. In the closed 
tube, water is given off at a low temperature. It is very 
readily decomposed by hot hydrochloric acid with the 
separation of silica, but without gelatinization. When 
the water in the mineral is driven off below 265° C., it is 
nearly all regained on exposing the mineral to the air. If 
the water, however, is driven off at a red heat, none is 
regained by the mineral. 
Name.—The name Wedls¢te is given to this mineral in 
honor of Professor H. L. Wells of the Sheffield Scientific 
School, Yale University. 
