126 On the Sea-Serpent of the American Seas. 



2. Orpiment, small imbedded crystals, from Thajowa, in Hun- 

 gary, , 3.460 



3. Orpiment, a massive, cleavable variety, 3.480 



4. Sulphur, of a pure sulphur-yellow colour, from Sicily, 2.072 



Class III. Order I. Resin. 



1. Mellite, several crystals, » 1.597 



2. Amber, honey-yellow, 1.111 



3. Retinite, a nearly transparent variety, with a strong peculiar 

 odour, from Halle, in Prussia, 1.079 



4. Bitumen, of the consistency of wax, 0.828 



5. Bitumen, of a black colour, and a splendent conchoidal frac- 

 ture. Its streak is pale brown, nearly yellow, 1.073 



6. Bitumen, hyacinth red, 1.160 



Class I. Order IV. 



1. Hemi-prismatic Natron-salt, artificial crystals, 1.423 



2. Another experiment gave 1.430 



3. Another, 1.495 



4. Prismatic Natron-salt, artificial crystals, 1.552 



5. Another experiment gave 1.562 



6. Sal ammoniac, fibrous masses, 1.528 



7. Rock-salt, hexahedrons obtained by cleavage, from Aussee in 

 Stiria, 2.257 



8. Sulphate of Copper, artificial crystals, 2.213 



9. Sulphate of Copper, a similar variety, 2.248 



10. Sulphate of Iron, (the common iron vitriol,) with a slight 

 admixture of sulphate of copper, 1.832 



11. Sulphate of Zinc, artificial crystals of a reddish-white colour, 



from Goslar, in the Hartz, 2.036 



12. Sulphate of Magnesia, 1.751 



13. Sulphate of Potash, 1.731 



14. Alum, artificial crystals, 1.753 



15. Alum, artificial crystals, 1.778 



16. Borax, artificial crystals, 1.716 



17. Glauhente, fragment of a large crystal, 2.807 



Art. XVII. — Additional Testimony respecting the Sea-Ser- 

 pent of' the American Seas. Communicated by Dr Hooker. 



When we remember the numberless impositions concerning 

 Natural History, which at various periods have been detect- 



