The Canary Islands off Africa's Moroccan coast were a principal stop for water and provisions during the age of discovery as well as the early voyages to the Chesapeake. They were also a way station for the Royal Clipper on our ocean passage to the Americas.

As we approached the archipelago, I examined a replica 15th century chart from the time of Sir Walter Raleigh. It showed profiles as seen from the sea for several of the Canaries, including a detailed view of the largest, Tenerife, which we were approaching from the east. I noted a rock pinnacle-Roque de Fuera-standing at sea just off the eastern tip that also appeared on the old chart.

As we sailed along the south coast, we passed a hillside on the chart labeled "the watering place." A peak on the skyline was labeled "most probably an old volcano." Indeed, the island has several eroded volcanic plugs, including Pico de Teide, a volcano that erupts periodically: 1492, the 1700s and 1909-with the most recent rumblings in 2003.

Geologically, the Canaries were born one after the other during volcanic eruptions through the sea floor beginning about 20 million of years ago. The last island, Hierro, rose about 800,000 years ago. This sequence occurred as Africa's tectonic plate slowly drifted over Earth's hot and unstable magma core.

I examined the chart again as we approached our destination, Santa Cruz de Tenerife. It showed the port we entered as an anchoring place and indicated a fort. Once alongside the quay, I found, adjacent the city's concert hall, the same fort that once defended Spain's interests on this island.

The English pirate, John Hawkins, showed up here in 1567 with his kinsman, the 22-year-old Francis Drake, after a 29-day voyage and one terrible gale out of Plymouth, England. Spanish policy tolerated visits by foreign vessels because it benefitted trade on these remote islands.

Hawkins needed water and some repairs for his storm-battered fleet, and sent a boat ashore with flowery greetings to the governor. But he strategically anchored by placing several Spanish ships between his vessels and the fort's guns. One night, an English sailor on watch noticed the Spanish ships dropping downwind in the dark, clearing a field of fire for the fort's guns at first light. The wily Hawkins followed the other ships' lead.

The next morning, the governor sent a boat with the query, "Now, my friend, why ever did you do that?" Hawkins finished his watering farther down the coast and left!

Christopher Newport, hired as admiral to command the trio of ships transporting Virginia Company's settlers in 1607, knew the Canary Isles from an earlier voyage. Departing Dover on Feb. 12, 1591, he and his fleet of four vessels "fell with Cape Cantin on the Coast of Barbarie (Morocco) and on the 27. day of the same moneth wee arrived at Santa Cruz roade (Tenerife) where having refreshed ourselves some 3. or 4. dayes, we put off to sea again, and about the 5. of March wee (had) passed by the Islands of the Canaries." Newport's passage to the Canaries took just 15 days, much faster than Hawkins' 24 years earlier.

Newport crossed the Atlantic with favoring trade winds in a speedy 29 days, landing his ships at Dominica, just as he would do with the Virginia adventurers.

He was also a plunderer-if not a pirate-losing an arm during one of his adventures. This voyage was no exception: Between February and September 1591 he had captured, burned or sunk 20 Portuguese and Spanish ships; trafficked in slaves from Guinea; and destroyed three Caribbean towns. I wonder how carefully folks looked at his record before naming Virginia's Christopher Newport University after him?

John Smith's account of their 1606-07 voyage to Virginia notes that Newport chose to visit the Canaries again.

Their voyage, starting at Blackwall Harbour on the Thames, was hard. Held by adverse wind, storms, Smith said that they were consuming their supplies for six weeks "in sight of England" with personalities grating upon each other.

The Rev. Robert Hunt, their preacher, was much credited for his peacemaking spirit, quieting the "many discontents (which) did then arise, had he not the water of patience; and his godly exhortations...quenched those flames of envie and dissention."

Smith thought the "disasterous designs (could they have prevailed) had even overthrowne the business" (of settling Virginia).

"We watered at the Canaries" Smith says simply in his "Generall Historie." They would have needed water-and fresh food-having in over two months consumed much of what they loaded for the greater voyage. Finding fresh water on ocean islands has been one of the great challenges for mariners since ancient times. Tenerife gets less than 8.5 inches of rain annually-a little more than a fifth of Maryland's average 40.8 inches.

What made the Canaries attractive to mariners were their hillsides clothed in forests of Canary pine (Pinus canariensis), a long-needled variety. Examining the terrain from the perspective of a 17th century mariner, I saw in these arrow-straight trees topmasts and yards for damaged ships limping in before their Atlantic crossings.

Tenerife and the other isles, are mountainous and high enough that, when the prevailing Northeast Trade Winds blow down upon them, the flowing air bounces upward. At higher and cooler altitudes-1,900-4,900 feet-moisture collected from passing 5,000 miles of ocean forms into clouds that bathe the trees. Their long pine needles sweep out the moisture, causing it to condense and fall on porous volcanic soils. As much as 400 liters a day can fall from a single tree.

Among the harmful, nonnative species that have been introduced to the Canaries is the California Monterey pine (Pinus radiata), which is outcompeting the Canary pine and does not serve the same water-capturing ecological role.

Percolating into the volcanic soils the resulting groundwater encounters impervious lava layers and collects in what is described as "700 underground lakes" by Rudolph Fuchs, a German expatriate who in his 26 years on the island, has become quite knowledgeable about its natural history.

In former times, these aquifers spontaneously overflowed through natural volcanic tubes and hillside springs. Mariners like Hawkins and Newport could send a boat ashore with barrels and load water unmolested as long as they had formally applied to and been granted access by the Spanish.

The islands' volcanic soils are also very fertile. Sugar cane, of Arab origin, was the first commercial crop.

Grapes were grown by the 1500s, and in 1603, the English introduced mid-Mediterranean and Greek varieties. They shipped the resulting "Canary" wines home. On London's Thames River there is even a section called the Canary Docks.

The North American colonies were a large market for these wines as well-late 17th century manifests and records in the Maryland region of the Chesapeake mention imported Canary wines. This lucrative trade was brought to an end when the English Parliament passed the Navigation Acts.

As demands increased, "water gallery" tunnels were bored as much as a mile into the hillsides. Some produced freshwater flows recorded at 7,727 gallons an hour. Subterranean waterfalls were sometimes encountered and tapped as irrigation sources into above ground cisterns where the supply could be metered out to various crops.

Hundreds, perhaps thousands of these tunnels still exist, but because of volcanic gases seeping into them and the lack of oxygen, they are hazardous. Six members of a party of 30 visitors died in the water galleries at Piedra de los Cochinas on Tenerife just nine months before my visit.

We might consider the Canaries, so close to Africa, very remote from the Chesapeake, but each autumn, a fleet of as many as 200 private sailing craft departs from La Palma-one of the Canary Islands-for the New World, and many of these find their way to the Chesapeake.

La Palma may also be a geological time bomb for the entire North Atlantic region. Its structure suggests to seismologists that a catastrophic eruption of the island's underlying volcano could cause one whole side of the island to slip into the sea. The resulting seaquake could trigger a tsunami which in about 9 hours could reach and inundate the entire U.S. East Coast. Sensors telemeter every 30 minutes, to warn of such an event.

The top of Tenerife's dominating volcano, Pico de Teide, rises 12,194 feet above the sea and is often wrapped in clouds. Until the 17th century, Teide was believed to be the highest mountain in the world. It is indeed Spain's highest mountain, and the third highest volcano on earth. Like Hawaii's Mauna Loa it was, in former times, almost always snow-capped but presumably as a result of global warming, it has been bare for a long time.

During a visit to the Orotava Valley, which stretches from the ocean up toward Pico de Teide, Fuchs took us to a wide field of pumice dunes deep with gravelly deposits almost as light as Styrofoam beads. Pumice is the result of expanding, gas-rich lava particles thrown from the volcano. Until its recognition as a finite geological artifact, it was mined by islanders and spread on their gardens. There, its light color and insulating properties protected soils against moisture loss, and when dew condensed atop it, the moisture percolated through the porous beads and was conserved beneath.

During a past active phase, a huge magma chamber collapsed on one side of Teide, opening a vast caldera or crater about 10.6 miles across and 29.8 miles in circumference.

The interior contains an immense lava plain called La Canadas, an extreme environment of jagged lava fields, lava plugs jutting upwards of 100 feet and desert dry meadows where just 11 native species, tolerant of severe conditions, survive.

Nonnative rabbits introduced to the island are threatening the survival of vegetation communities in the caldera. Today, expensive control programs are working to prevent this loss. Introduced mountain goats are overgrazing plant communities in other parts of the island.

Pico de Teide sometimes wears what locals call a sombrero of cloud that lore says foretells rain the next day. We saw one on this visit and Fuchs said with a smile, "watch tomorrow's weather." We were unable to test the proverb because Royal Clipper set sail that night bound for the wide Atlantic.

Bird Dogs?

The Canary Islands are not named for the yellow bird, although these popular pets are descended from a native island finch, the "tame" or Atlantic canary, Serinus canaria. There are believed to be 80,000-90,000 pairs in the archipelago today.

The name dates back to the Presa Canario, a race of boxer-like canines, descended from Greek war dogs, brought to the islands in 85 B.C. They served as farm dogs for the island's inhabitants.

This led to a description as "canariae insulae" or the isles of dogs, by North African Christian apologist Arnobius of Sicca Veneria.

The islands were settled during Neolithic times by people of North African Berber stock. These inhabitants, called guacha by European explorers, fought fiercely against Spanish invaders. Their knowledge of the islands' geography enabled them to use stilt-like vaulting poles to leap over the deep volcanic gullies while heavily armed troops slogged laboriously over the rough terrain.

It wasn't until 1496 that the islands were wholly subjugated.

Editor's Note: This is the second in a series of columns detailing Kent Mountford's trip on the sailing ship, Royal Clipper, tracing the route of the early voyages from Europe to the Chesapeake. For the first leg of his voyage, read "Past is Prologue," March 2008.