Knoirledi/f. 



Fig. I. — Cirro-iMimiili pa><<ins hc'fori- tlie Sun, lS9y, Septi>mhi>r, 2>il. -tli. 3111., Mean Local Time. 



Fir;. 2.-T),.inr1..r-t..nTi Cumiili rolliiiif ;vr Piiri-. IS!)!), SriitcmliiT, 2^.1 3li. 2in., Lnciil Tim.'. 



CLOUD PHOTOGRAPHS TAKEN AT M. FLAMMARIONS 

 OBSERVATORY, JUVISY, FRANCE. 



