274 rnrsicAL geography of the sea, and its meteorology. 



place from the Kew Obsei-vatory in England, it has been ascer- 

 tained that there the cloud region is from 2000 to 6500 feet high, 

 with a thickness varying from 2000 to 3000 feet, and that its 

 temperature at the top is not lower than it is at the bottom of the 

 cloud, notwithstanding its thickness. AVe are also indebted to 

 Piazzi Smyth for interesting observations on the cloud region in 

 the belt of north-east trades and of the upper counter current 

 there. They were made from the Peak of Teneriife, at the height 

 of 12,200 feet, during the months of August and September, 1856.* 

 The cloud region of the trades was between 3000 and 5000 feet 

 high ; of the upper or south-west current, it was above the 

 mountain. Islands only a few hundred feet high are generally 

 cloud-capped in the trade-wind regions at sea ; another indication 

 that, with a given amount of moisture in the wind, the cloud 

 region is higher at sea than it is over the land. For most of the 

 time during his sojourn on the Peak, the sea was concealed from 

 view by the cloud stratum below, though the sky was clear over- 

 head. Farther to the north, in the Atlantic, however, as in the 

 fog region about the meeting of the cool and warm cuiTents near 

 the Grand Banks, the look-out at the mast-head often finds himself 

 above the fog or cloud in which the lower parts of the ship are 

 enveloped. Going still farther towards the north and reaching 

 the ice, the cloud region would again, for obvious reasons, mount 

 up until you reached the open sea there, when again it would 

 touch the earth with its smoke. 



510. Fogs in the harbour of Callao. — In the harbour of Callao, 

 in Peru, which is filled with the cool waters of Humboldt's 

 current, I have seen the bay covered with a fog only a few 

 inches high. I have seen fogs there so dense, and with outlines 

 so sharp, as to conceal from view the row-boats approaching the 

 ship's side. These fogs, especially early in the morning, will 

 conceal from view not only the boat, but the persons of the crew 

 up to the neck, so as to leave nothing visible but two rows of 

 trunkless heads nodding catenaries at the oars, apparently skim- 

 ming through the air and dancing on the fog in a manner at once 

 both magical and fantastic. At other times the cloud stratum is 

 thicker and higher. Then may be seen three masts coming into 

 port with topgallant-sails and royals set, but no ship. These sails, 

 nicely trimmed and swelling to the breeze in the skj^ swim along 

 over the clouds, and seem like things in a fairy scene. However, 

 * Teneriffe, An Astronomer's Experiment. London, 1858. 



