[111] According to the details given us by De Angelis (1837, Introduction to the _Diario del viaje al Rio Bermejo de Fray Francisco Moritto_, Coll. de Angelis, vol. vi) a convoy of fourteen wagons from Salta to Tucuman required three relays of oxen. The first, comprising a hundred animals, went from Salta to Tucuman; the second, of 130 animals, went from Tucuman to the Buenos Aires frontier; the third (84 animals), went on to the capital. The first and last relays were hired animals, the second alone being the property of the _tropero_. The stages were rarely more than four or five leagues of five kilometres each (thirteen to sixteen miles). At this rate it took a convoy forty to fifty days to go from Buenos Aires to Mendoza, thirty days from Rosario to Tucuman, three months (with the necessary rests) from Buenos Aires to Salta.[112] When water ran short, the journey might be greatly prolonged, as the animals could do less work, or not work at all if the _aiguades_ had dried up. The season was a matter for consideration. In the Buenos Aires district the winter made the ground sodden and traffic difficult. Farther north, winter is the dry season, so that pasture was scarce, and it was difficult to feed the _tropas_. The summer had difficulties of its own. In January and February the floods of the Rio Dulce often made it impossible to cross the ford at Santiago. The carriers preferred to start from the northern provinces about the end of the summer, in April or May. The best season for leaving Buenos Aires was the spring, from August to November. In this way each _tropa_ could make the double journey once a year. [112] Thirty days from Buenos Aires to Mendoza, and seventy days from Buenos Aires to Jujuy, says Barrero (F. Barrero, _Descripcion de las Provincias del Rio de la Plata_, end of the eighteenth century, published by the Ministry of Foreign Affairs, Buenos Aires, 1911). There had been attempts to speed up the transport before the railways were made. The _galera_ (diligence), with its swarm of horses harnessed with the _cincha_ (saddle to which the lasso was attached), did not carry goods. It did not replace the convoy of wagons, but the _tropilla_ of spare horses which travellers on the plain drove before them. The _galera_ went from Rosario to Cordoba in three days and to Mendoza in ten days, and from Cordoba to Salta in fourteen days. About 1860 a quicker goods service was organized, light wagons drawn by mules replacing the ox-wagons. They made the journey from Rosario to Cordoba in six days. Similarly, on the Pampa, the ox-wagons had been replaced before 1889 by quicker wagons, drawn by horses, to convey wool from the ranches to the railway stations.