( 88 ) 
Fig. 11. TJranyl sulphate. 
Temperature 80° K. 
Second spectrum, Rowland grating. 
Channeled spectrum in the green-blue. 
Fig. 12. Absorption and emission of autunite (calcium uranyl phosphate) at 14° K. 
Second spectrum, Rowland grating. 
a) emission spectrum, b ) absorption spectrum, « and /3, bands common 
to both spectra (reversible bands). 
Fig. 13. Absorption and emission of autunite at 80° K. 
First spectrum, Rowland grating. 
a) and b) two of the chief absorption spectra of the crystal plate, 
c) phosphorescence spectrum, a) reversible band. 
ERRATUM. 
In the Proceedings of the Meeting of Oct. 31, 1908. 
p. 335 line 5 from the bottom: for Pt'd read Ptd- 
the head of Table I read: Comparison between JPt'i and Pfd- 
p. 341 line 1 from the bottom: for 1807 read 1907. 
(June 25, 1909). 
