8. _Guayacan_, or _Guallacan_ (_Lignum vitæ_).—Common; close-grained; heavy; works well when green; grows to four or five feet in diameter; used for gun-carriages, wheels, etc. 9. _Algarobo._—Excellent wood; hard and tough; reddish brown, with streaks; large; common; used for gun-carriages. 10. _Mangle Caballero_ (_Mangrove_).—Good as the Nispero; abundant near water; gives pieces thirty to forty feet long, and one foot square; used for vessels. 11. _Alcomorque_ (cork tree).—Supplies large beams, which wear well. 12. _Malvicino._—Yellow; abundant; wears well; employed in building. 13. _Caoba_ (mahogany).—Large; not heavy; good for interiors; if not properly seasoned, is brittle. 14. _Robles._—Large; not heavy; easily worked; used for paddle by the Indians; stand well in air; two varieties, one not good. 15. _Cocobolo Prieto._—Tough, hard; beautifully figured (like rosewood); three feet in diameter; fragrant when green; used for carpentry and cabinet work. 16. _Tutumia_ (calabash tree). 17. _Cano Blanco._—Cane; good for lathing when split. 18. _Quira._—Tough, close-grained, heavy; different colors, from light brown to very dark; very high; from one to three and one-half feet in diameter; plentiful; used in house-building. 19. _Madrono Fino._—Like box; one and one-half foot in diameter; excellent wood for turning. Mr. Loyd gives a list of ninety-five varieties of woods, of which list the above are the most valuable. GEOLOGY. A mere enumeration of the geological specimens, which is all that present knowledge upon this subject will permit, is not thought desirable in this paper. Speculations and theories, if not premature, would be out of place. The physical geography of Central America is the proper subject for a treatise. We have already seen how the table-lands of Guatemala, from four to five thousand feet above the level of the sea, sink to an insignificant height at Panama and Nicaragua. “There is no spot on the globe,” says Humboldt, “so full of volcanoes as this part of America, between 11° and 13° of latitude.” Two or three volcanoes, Fuego and Agua, in the State of Guatemala, are 14,000 and 12,000 feet high. Some of the volcanoes of Nicaragua reach a height of 7,000 feet. A common and remarkable characteristic of all of them is, that they rise in a conical form from the plain.