[1536.] In April, 1528, as we have seen, Pánfilo de Narvaez had landed on the west coast of Florida, probably at Tampa Bay, and attempted with three hundred men to reach Pánuco by land. The company gradually melted from famine, sickness, and battles with the savages, until only Alvar Nuñez Cabeza de Vaca with a few companions remained. They were held as slaves by the natives of the Gulf coast for six years; and then escaping, traversed Texas, Chihuahua, and Sonora, by a route which has not been very definitely fixed. Cabeza de Vaca with three companions reached the Spanish settlements in northern Sinaloa early in 1536, and their reports served as a powerful incentive to more extended exploration. _Relatione che fece Alvaro Nvnez detto Capo di vacca_, in _Ramusio_, tom. iii. fol. 310-30; _Purchas_, _His Pilgrimes_, vol. iv. p. 1499; _Cabeça de Vaca's Relation_, New York, 1871; _Ternaux-Compans_, _Voy._, série i. tom, vii.; _Oviedo_, _Hist. Gen._, tom. iii. p. 582 et seq.; _Barcia_, _Historiadores Prim._, tom. i. _Peter Martyr_, _De Rebus Oceanicis_, Paris, 1536, contains nine decades. This work, with _Sacro Bosco_, _Sphera Volgare_, Venetiis, 1537, and _Nunez_, _Tratado da Sfera_, Olisipone, 1537, closes the bibliographical part of this Summary, in which, following Harrisse as the latest authority, I have endeavored to mention all the original works by which the geographical results of voyages of discovery were made known prior to 1540. [1537.] After the abandonment of California by the colony, Cortés sent two vessels under Hernando de Grijalva and Alvarado (not Pedro) to Peru with supplies and reinforcements for Pizarro. There are vague reports that Grijalva sailed westward from Peru and made a long cruise in the Pacific, visiting various islands which cannot be located. _Herrera_, _Hist. Gen._, dec. v. lib. viii. cap. x.; dec. vii. lib. v. cap. ix.; _Galvano's Discov._, pp. 202-3; _Burney's Discov. South Sea_, vol. i. p. 180. [1538.] Fernando de Soto landed on the west coast of Florida, crossed the peninsula to that part discovered by Aillon in 1526, wandered four or five years in the interior of the southern United States and followed the course of the Mississippi, probably as far up as to the Ohio. Here Soto died, and the remnant of his company, after penetrating farther west to the buffalo country, floated down the Mississippi and returned to Mexico in 1543. Soto's travels are esteemed by Kohl as "the principal source of knowledge regarding these regions, for more than a hundred years." _Discov. and Conq. of Terra Florida_, _Hakluyt Soc._, London, 1851; _Selection of Curious Voy._, _Sup. to Hakluyt_, London, 1812, p. 689; _Purchas_, _His Pilgrimes_, vol. iv. p. 1532; _Ferdinands von Soto Reise nach Florida_, in _Sammlung_, tom. xvi. p. 395.