CHAP. I. ] FROM PORTSMOUTH TO TENERIFFE. 1538 
of about 7000 feet, 5000 feet below the summit of the Peak. 
With the friendly assistance of the British consul, their ar- 
rangements were all satisfactorily made. They went across 
the island to Orotava, whence they commenced the ascent of 
the mountain. They spent four nights camped on the high 
grounds. It was too early in the season to attempt the ascent 
of the Peak, and rather too early for natural-history work: the 
chief object was to get into the modus operandi of such expe- 
ditions in preparation for the future. Still, collections weie 
made both in zoology and in geology, and the party were 
greatly interested in the wonderful atmospheric effects from 
their camping-ground above the lower stratum of clouds. The 
ship weighed anchor on the morning of Monday, the 10th, and 
took a sounding and dredging cruise among the islands. We 
dredged between Teneriffe and Palma, and passed close under 
Palma, near enough to see the outline and bounding wall of its 
wonderful crater; past Gomera, a fine rugged island, the coast 
showing the usual alternation—deep ravines and lava spurs cov- 
ered with vines and maize. Past Hierro, or Ferro, another fine 
bold island, interesting as having been long regarded as the 
western point of the Old World, and on that account chosen 
as the zero in reckoning longitude. The zero-line passing 
through Hierro is still used in some countries, though the me- 
ridian of Greenwich is now almost universally employed for 
practical purposes, such as the construction of charts. The po- 
sition of Hierro appears to have determined the line of division 
of the world on maps into an eastern and a western hemisphere. 
We had splendid moonlight during our cruise, and although 
the Peak remained almost constantly shrouded in mist during 
the day, it shone out at night as a dazzling white cone through 
the rifts in the clouds. 
We returned and anchored in Santa Cruz Bay on the morn- 
ing of Thursday, the 13th. 
Owing to the uncertain and boisterous weather, the temper- 
