VOL, 



LVl,] 



PHILOSOPHICAL TKANSACTIONS. 



355 



4- foot Newtonian telescope, the longitude from Paris being l'' l"" 56^ And 

 Mr. Wargentin's at Stockholm, with a Dollond's 10-foot tube, the difference of 

 longitude from Paris being l** 2"° 51% and from Greenwich l'' 12'" 7^ 



Finally, Mr. W. is persuaded that this method of determining longitudes by 

 observations of Jupiter's satellites, is to be preferred to the others; that it is more 

 clear and general ; and especially as it indicates at once which of the observa- 

 tions are too great or too little. 



Observationes comparatte primi Sat. Jovis. 



Tern. comp. Err. comp. Locus obs. 

 "" 0"l'."— Paris. 



';?8 + Vienna. 

 O 30 + Vienna. 

 12 — Stockh. 

 7 — Paris. 

 4 — Tyrna. 

 25 + Vienna. 

 12 + Tyrna. 

 1 - Barbed. 

 10 + Vienna. 

 8+ Paris. 

 50 + Barbad. 

 6 + Barbad, 

 43 + Tyrna. 

 13 — Paris. 

 2 — Barbad. 

 2 20 — Barbad. 

 2 — Barbad. 

 11+ Stockh. 

 32 + Barbad. 

 (» 19 — Barbad. 

 14 + Barbad. 

 13 + Barbad. 



Tempus observat. 

 r 2" ll''25'"59' 

 ' 2 11 19 10 

 5 47 15 

 13 39 43 



8 7 '20 



9 59 38 

 23 1 1 32 36 

 25 6 .0 51 

 25 11 31 20 



8 10 9 19 



8 46 6 



9 47 41 

 17 10 41 48 

 17 11 43 6 



II 44 22 

 6 13 22 

 6 6 34 

 6 11 45 

 8 30 42 era 

 10 4 51 

 10 6 41 

 6 26 48 

 6 31 45 



4 



7 



9 



16 



n 

 10 



17 

 19 

 19 

 19 

 24 



&.13 

 13 



Tem. comp, 

 1I''26"'I7 

 11 19 37 



5 47 29 

 13 39 33 



8 7 29 



9 59 52 

 11 52 52 



6 21 15 

 11 31 51 

 10 9 50 



8 46 24 



9 47 18 



10 41 51 



11 42 45 

 11 44 40 



6 13 39 



6 6 59 



6 11 44 



. 8 30 13 



10 4 53 



10 6 48 



6 26 34 



6 32 10 



Err. comp. Locus obs. 

 0'°18'+ Stockh. 

 27 + Vienna. 

 14 + Vienna. 

 13 — Barbad. 

 19 + Barbad. 

 14 + Barbad. 

 O 16 + Barbad. 

 24 + Barbad. 

 31 + Stockh. 

 31+ Barbad 

 18 + Paris. 

 23 — Tyrna. 

 3 + Paris. 

 21 — Tyrna. 

 18 + Stockh. 

 17 f Stockh. 

 25 + Vienna. 

 1 — Tyrna. 

 29 — Barbad 

 2+ Tyrna. 

 7+ Stockh. 

 14 — Vienna. 

 34 — Tyrna. 



XXXV. On the Coluber Cerastes, or Horned Fiper of Egypt. By John Ellis, 



Esq., F. R. S. p. 287. 



The coluber cerastes,* or horned viper of Egypt, which Mr. E. presented a 

 specimen of to the r. s. is very rare, and scarcely to be found in any of the cabi- 

 nets of Europe. Besides, the authors who have treated on the cerastes, as Al- 

 pinus and Bellonius, have given such unsatisfactory descriptions of it, and inac- 

 curate figures, that an exact drawing from nature, together with the best and 

 latest systematical account of it, may be agreeable, as well to the lovers of anti- 

 quity as natural history. 



The ancient Egyptians most certainly esteemed it a hieroglyphic of some im- 



* The coluber cerastes is a native of the sandy desarts of Arabia and many parts of Africa; it is 

 furnished with poisonous fangs, like the common vipwr. It is admirably figured in Mr. Bruce's 

 Travels. 



zz 2 



