Another description of the same character will exhibit some of the difficulties: “Occasionally a swamp, growing an impenetrable mass of vegetation, delayed our progress and expended our energies in fruitless hacking. The only way to get through many of these cienegas was to fall on one’s back into the middle of the matted vegetation, and then compress a place the length of one’s self, which those behind trod down. After persevering in this manner for several hundred yards, an inlet would be reached with a soft, muddy bottom, and waist deep from the flood. On the other bank, the same mode of progress had to be adopted, until prickly palms, and still more prickly creepers, made a variety in the difficulty and suffering.” Strain met with similar obstruction. “Hitherto, Strain had led the party, every day cutting a path with his cutlass. This was most laborious, and Mr. Truxton insisted on going ahead in his place. The undergrowth was exceedingly dense, and composed, for the most part, of ‘pinello,’ or little pine, a plant resembling that which produces the pineapple, but with longer leaves, serrated with long spines, which produce most painful wounds, especially as the last few days’ march had stripped the trousers from many of the party.” The best way to clear these obstructions has been found to employ natives, with machetes. This method, invariably adopted in Central America, has been recommended by Admiral Davis, who also advises the explorer to carry with him a good supply of canned and concentrated provisions. BUILDING MATERIAL. Suitable stone is found without difficulty. Hydraulic cement will probably have to be imported, although hydraulic limestone is said to have been found in the States of Vera Cruz and Oazaca. The explorer will find difficulty in discovering building sand. The sea beaches may afford suitable sand for hydraulic work. Bricks can be manufactured, without difficulty, at many points. WOOD AND TIMBER. The following, from the account of Lloyd and Sidell, gives the local names and character of the most useful species: 1. _Guachapali._—Abundant; four or five feet in diameter, like walnut; good under water. 2. _Macano_, or _Cacique_.—Crooked, medium size; good in ground or water; much used. 3. _Espino Amarillo._—Not abundant; good in water; yellow; not liable to decay, or to be attacked by insects; straight; easily worked; seven kinds. 4. _Cedro Espinoso._—Large, straight, light; heart alone good in open air and under ground. 5. _Cedro Cerollo._—Large, crooked, durable. 6. _Cedro real, Amargo._—Finest cedar of the country; used for many purposes in carpentry and boat-building; grows to five or six feet in diameter, and is very common. 7. _Nispero._—Large; not easily worked; stands well when sheltered; insects do not touch it; resists transverse strain; two kinds much esteemed.