All the curtains which face the western and northern part of this fortress are, without question, the weakest part of its defenses; but on the supposition (which is believed to be a remote contingency) that European armies may move to attack it in earnest--and it may be regarded as an enormous undertaking by our enemies here, who are most laughable on account of their lack of discipline and of forts--the natural defenses are apparently even more than sufficient. For it has on the west the waters of the bay for a moat, and on the north a river that is broad and deep; and with this all fears may be laid aside. There is also maintained in this city, at the expense of the royal treasury (as being a necessity), a foundry for artillery, grenades, and cannon balls of all calibers; and an iron-furnace, where men are continually forging, according to the occasion, many hand-weapons and some firearms. The metals for these are transported from countries beyond the sea. Besides these, a scant half-legua to the south, is the powder-factory, which is enclosed by a triangular redoubt of stone and mortar, with seven mounted iron cannons, and fortified by three demi-bastions. This factory supplies gunpowder to Manila and the forts dependent on it; to the ships of his Majesty which sail annually to the port of Acapulco and the Marianas Islands; to the armadas which, when any danger from enemies arises, are made ready on the opposite shore; and to the public festivals. More than enough to cover the expense is received from those who wish to buy it, to whom it is furnished for their money. The ingredients of its composition are produced in the country, except the saltpetre, which is brought from foreign countries. Artillery, mounted and dismounted, of this fort, with whatever is necessary for handling it Bronze cannons Caliber Iron Caliber cannons 1 3 2 2 1 4 13 4 1 5 6 5 2 8 10 6 1 9 11 8 1 14 4 10 1 16 4 12 15 8 4 14 7 20 5 18 3 22 4 20 2 24 2 30 6 25 2 stone-mortars, 90 for moat-guards -- -- 43 bronze cannons 65 iron cannons Military supplies kept in reserve, independent of those used in actual service