172 



Presents. 



[Mar. 10, 



Pritchard, and others. He further shows that observations made by 

 people who are colour-blind in the red tend to diminish the value of 

 the coefficient of transmission, and that the difference between stellar 

 and solar light cannot account for the apparent discrepancy. It would 

 appear that Professor Pritchard's maximum value for the coefficient 

 of transmission at Cairo does not differ much from his. 

 . The values of the different colours in the spectrum which Rood has 

 adopted from Vierordt's method are then discussed, and corrected 

 according to the author's determination of the values on a day in 

 June. 



A series of tables close the paper, in which the original observations 

 and the deduced values are given. 



Presents, March 10, 1887. 



Transactions. 



Calcutta: — Asiatic Society of Bengal. Journal (Natural History). 

 Yol. LV. Part 2. No. 3. 8vo. Calcutta 1886. Journal (Philo- 

 logical). Vol. LV. Parti. No. 3. 8vo. Calcutta 1886; Pro- 

 ceedings. 1886. Nos. VIII-IX. 8vo. Calcutta. The Society. 



Dublin: — Royal Irish Academy. Proceedings (Literature, &c). 

 Vol. II. No. 7. 8vo. Dublin 1886. Proceedings (Science). 

 Vol. IV. No. 5. 8vo. Dublin 1886 ; Transactions (Literature, 

 &c). Vol. XXVII. Parts 6-8. 4to. Dublin 1885-86. Trans- 

 actions (Science). Vol. XXVIII. Parts 21-25. 4to. Dublin 

 1885-86 ; " Cunningham Memoirs." Nos. II-III. 4to. Dublin 

 1886. The Academy. 



London: — Entomological Society. Transactions. 1886. Part V. 

 8vo. London. The Society. 



Odontological Society. Transactions. Vol. XVI. 8vo. London 

 1884. Ditto. Vol. XVII. No. 1. 8vo. London 1884. 



The Society. 



Manchester: — Geological Society. Transactions. Vol. XIX. 



Parts 3-4. 8vo. Manchester 1887. The Society. 



Paris : — Societe Francaise de Physique. Collection de Memoires 



relatifs a la Physique. Tome III. 8vo. Paris 1887. 



The Society. 



Pesth: — Konigl. Ungar. Geologische Anstalt. Poldtani Kozlony. 

 Kotet XVI. Fuzet 7-12. 8vo. Budapest 1886 ; Mittheilungen 

 aus dem Jahrbuche. Band VIII. Heft. 4. 8vo. Budapest 1887; 

 Catalog der Bibliothek. Suppl. 1. 8vo. Budapest 1886. 



The Institution. 



Stockholm: — Kongl. Vetenskaps-Akademie. Ofversigt. Arg. 43. 

 No. 10. 8vo. Stockholm 1886. The Academy. 



