Encouraged by this example, numerous other landholders of the district have succeeded in cultivating similar plantations, and the result has proved highly beneficial, not only in the transformation of the country but from the commercial point of view as well. For districts that until recently were absolutely worthless are now valued at anything from ten dollars to forty dollars the hectare. A peculiar characteristic of these Maldonado sand-dunes is to be met with in the fulgurites that are found there--the vitrified sand-tubes caused by the action of lightning that are referred to by Darwin on the occasion of his visit to the spot. Similar phenomena obtain in a few other corners of the world, but those found here are by far the largest in size, some extending to no less than five feet in length. Owing, however, to their extremely fragile nature, it is impossible to extract these larger specimens in any fashion but in comparatively small fragments. Mr. C. E. R. Rowland, the British Vice-Consul at Montevideo, has taken especial interest in these fulgurites of the Maldonado Sands. The British Museum contains some very fine specimens sent by him, and he has supplied the national museum at Montevideo with its first specimens of these curiosities. This same gentleman, by the way, quite recently discovered two distinct species of Uruguayan lizards that, sent for classification to the South Kensington Natural History Museum, were discovered to be of kinds that until then had been perfectly unknown. They remain in the museum to which they were sent, dignified by the name of their discoverer. CHAPTER XVII MERCEDES AND THE SWISS COLONY The journey to Mercedes--The outskirts of Montevideo--Santa Lucia--A pleasant town--Native quince and gorse--San José--The terminus of a great highway--Some feats of engineering--The urban importance of San José--A modern flour mill--Mal Abrigo--Character of the soil--A country of boulders--Some animals of the Sierra de Mal Abrigo--The surroundings of Mercedes--A charmingly situated town--The terminus of the line--Some characteristics of Mercedes--Urban dwellings--The delights of the patio--The disadvantages of economy in space--Streets and plazas--The hospital--A well-equipped institution--View from the building--An island in Rio Negro--The Port of Mercedes--River craft--Some local scenes--An equine passenger--Formidable gutters--The industries of the town--The Hôtel Comercio--Colonia Suiza--Situation of the Swiss Colony--Uruguayan Campo dwellings--Method of construction--Simplicity of household removals--Aspect of deserted huts--The houses of the Swiss Colony--Habits in general of South American colonists--The range of nationalities--Liberty accorded--Population of the Colonia Suiza--Its industries--A dairy-farming community--An important butter factory--An instance of a rapid rise from poverty to riches.