After some time usefully employed in acquiring and diffusing a competent knowledge of cosmopographical, nautical, and astronomical science, Don Henry resolved to devote a considerable portion of the revenue which he enjoyed as Grand Master of the Order of Christ, in continuing and extending those projects of nautical discovery which had long occupied his attention. Accordingly, about the year 1418, a new expedition of discovery was fitted out for the express purpose of attempting to surmount the perils of Cape Bojador. In this expedition Juan Gonzales Zarco and Tristan Vaz Texeira, two naval officers of the household of Don Henry, volunteered their services; and, embarking in a vessel called a barcha258, steered for the tremendous cape. The Portuguese were hitherto ignorant of the prevailing winds upon the coast of Africa, and the causes by which their influence is varied or increased. Near the land, and between the latitudes of 28° and 10° north, a fresh gale almost always blows from the N.E. Long sand-banks, which extend a great way out to sea, and which are extremely difficult to be distinguished in the mornings and evenings, and the prevailing currents, were powerful obstacles to the enterprise of these navigators. About six leagues off Cape Bojador, a most violent current continually dashes upon the breakers, which presented a most formidable obstacle to the brave but inexperienced mariners. Though their voyage was short, they encountered many dangers; and, before they could reach the cape, they were encountered by a heavy gale from the east, by which the billows of the Atlantic became too heavy to be resisted by their small vessel, and they were driven out to sea. On losing sight of their accustomed head lands, and being forced into the boundless ocean for the first time, the ships company gave themselves up to despair; but, on the abatement of the tempest, they found themselves unexpectedly within view of an island, situated about 100 leagues west from the coast of Africa. With extreme joy they beheld the coast of this island extending about twenty miles in length, to which they gave the name of Puerto Santo, because first discovered upon the feast of All Saints. This is the smaller of the Madeiras, being only about two miles broad; and, as the only roadstead is upon the south-west side, the Portuguese probably anchored upon that side to be under the lee shelter of the island from the remnants of the tempest from which they had happily escaped.

The island of Puerto Santo, or of the Holy Haven, is almost directly west from Cape Cantin; whence it would appear that these Portuguese navigators could hardly have passed much beyond Cape de Geer, when driven off the coast by this fortunate easterly tempest. Had they even advanced as far as Cape Non, they would almost certainly have been driven among the Canaries. It is perfectly obvious that they never even approached Cape Bojador in this voyage; unless we could suppose, after having been driven directly west from that cape, that they shaped a northern course, after the subsidence of the tempest, and fell in with Puerto Santo while on their return to Portugal.

Greatly pleased with the soil and climate of this island, and with the gentle manners of the natives, whom they described as in an intermediate state of civilization, and entirely destitute of any appearance of savage ferocity, Zarco and Vaz immediately returned to Portugal, where they made a report of the incidents of their voyage; and to confirm their opinion of the value of their discovery, they requested permission from Don Henry to return for the purpose of establishing a settlement in Puerto Santo. By this discovery an advanced and favourable station was secured towards the south, whence any discoveries along the coast of Africa might be prosecuted with greater ease and safety, and from whence the dangers of the hitherto formidable cape Bojador might be avoided, by keeping a southerly or S. W. course from Puerto Santo. From these considerations Don Henry granted their request; and, yielding to the adventurous spirit which this accidental discovery had excited, he permitted several persons to join in a new projected voyage, among whom was Bartholomew Perestrello, a nobleman of his household.

Three vessels were soon fitted out259, which were placed under the respective commands of Zarco, Vaz, and Perestrello. These commanders had orders to colonize and cultivate the newly discovered island, and were furnished with a considerable assortment of useful seeds and plants for that purpose. They happened likewise to take with them a female rabbit great with young, which littered during the voyage; and which being let loose with her progeny, multiplied so rapidly, that, in two years, they became so numerous as to occasion serious injury to the early attempts at cultivation, and to baffle every hope of rendering Puerto Santo a place of refreshment for the Portuguese navigators; insomuch that a resolution was formed to abandon the newly established settlement. After having landed the different animals and seeds which had been sent out by Don Henry, and seeing them properly distributed, Perestrello returned into Portugal to make a report to the prince, and Zarco and Vaz remained to superintend the infant colony.

Soon after the departure of Perestrello, the attention of Zarco and Vaz was strongly excited by observing certain clouds or vapours at a great distance in the ocean, which continually presented the same aspect, and preserved exactly the same bearing from Puerto Santo, and at length occasioned a conjecture, that the appearance might proceed from land in that quarter. Gonsalvo and Vaz accordingly put to sea and sailed towards the suspected land, and soon discovered that the appearances which had attracted their notice actually proceeded from a considerable island entirely overgrown with wood, to which, on that account, they gave the name of Madeira260. After bestowing considerable attention upon the soil and other circumstances of this island, which was utterly destitute of inhabitants, Gonzalvo and Vaz returned to Portugal with the welcome intelligence, and gave so favourable a report of the extent, fertility, and salubrity of Madeira, that Don Henry determined to colonize and cultivate it. Accordingly, with the consent of the king of Portugal, the island of Madeira was bestowed in hereditary property upon Zarco and Vaz; one division named Funchal being given to Zarco, and the other moiety, named Machico, to Vaz.

In the year 1420 Zarco began the plantation of Madeira, and being much impeded in his progress by the immense quantity of thick and tall trees, with which it was then everywhere encumbered, he set the wood on fire to facilitate the clearing of the surface for cultivation. The wood is reported to have continued burning for seven years261, and so great was the devastation as to occasion great inconvenience to the colony for many years afterwards, from the want of timber. Don Henry appears to have been a prince of most uncommonly enlarged and liberal views; not only capable of devising the means of making maritime discoveries, which had never been thought of before his time, but of estimating their value when made, and of applying them to purposes the most useful and important for his country. Reflecting upon the reported fertility of the soil, and the excellence of the climate of Madeira, and comparing both with the judicious foresight of a philosopher, politician, and naturalist, in reference to the most valuable productions of similar climates and soils, he wisely conceived, and successfully executed the idea of introducing the cultivation of sugar and wines into this new colony; For these purposes, Portugal would readily supply him with vines; and with people conversant in their management: But he had to procure sugar canes, and persons experienced in their cultivation, and in the process of manufacturing sugar from their juice, from the island of Sicily, into which that article of culture had been introduced by the Arabs.