I here made the acquaintance of colonel McCrae, who was largely concerned in the india-rubber trade. He afterwards distinguished himself during the revolutionary outbreak of 1869. He collected the rubber men and came to the assistance of the government, helping greatly to put down the insurrection. Originally a British subject, but now a naturalised Nicaraguan, he has filled with great credit for some time the post of deputy-governor of Greytown, and I always heard him spoken of with great esteem both by Nicaraguans and foreigners. He showed to me pieces of cordage, pottery, and stone implements brought down by the rubber men from the wild Indians of the Rio Frio. Castillo is one of the centres of the rubber trade. Parties of men are here fitted out with canoes and provisions, and proceed up the rivers, far into the uninhabited forests of the Atlantic slope. They remain for several months away, and are expected to bring the rubber they obtain to the merchants who have fitted them out, but very many prove faithless, and carry off their produce to other towns, where they have no difficulty in finding purchasers. Notwithstanding these losses, the merchants engaged in the rubber trade have done well; its steadily increasing value during the last few years having made the business a highly remunerative one. According to the information supplied to me at Greytown by Mr. Paton, the exports of rubber from that port had increased from 401,475 pounds, valued at 112,413 dollars, in 1867, to 754,886 pounds, valued at 226,465 dollars, in 1871. India-rubber was well-known to the ancient inhabitants of Central America. Before the Spanish conquest the Mexicans played with balls made from it, and it still bears its Aztec name of Ulli, from which the Spaniards call the collectors of it Ulleros. It is obtained from quite a different tree, and prepared in a different manner, from the rubber of the Amazons. The latter is taken from the Siphonia elastica, a Euphorbiaceous tree; but in Central America the tree that yields it it is a species of wild fig (Castilloa elastica). It is easily known by its large leaves, and I saw several whilst ascending the river. When the collectors find an untapped one in the forest, they first make a ladder out of the lianas or "vejuccos " that hang from every tree; this they do by tying short pieces of wood across them with small lianas, many of which are as tough as cord. They then proceed to score the bark, with cuts which extend nearly round the tree like the letter V, the point being downwards. A cut like this is made about every three feet all the way up the trunk. The milk will all run out of a tree in about an hour after it is cut, and is collected into a large tin bottle made flat on one side and furnished with straps to fix on to a man's back. A decoction is made from a liana (Calonyction speciosum), and this on being added to the milk, in the proportion of one pint to a gallon,