S86 A NATURALIST IN THE PACIFIC 



The volcano was quiescent during my visit and could have exercised 

 but little influence on the air-currents. 



The Shadow of the Mountain. — Every morning and evening, in clear 

 ■weather, for about twenty minutes after sunrise and before sunset, the 

 shadow of the mountain was thrown back against the sky of the opposite 

 horizon. It seemed as if some Titanic brush, at work in the sky far 

 away, had painted in the profile of the mountain with a very uncanny blue. 

 At sunset the peak was the last to disappear. Commodore Wilkes, who 

 only records it once, namely, at sunset on the ist of January, describes it 

 as "a beautiful appearance of the shadow of the mountain projected on the 

 eastern sky ... as distinct as possible, its vast dome seemed to rest 

 on the distant horizon.'' This phenomenon is, of course, well known 

 in the case of other isolated mountains. According to Murray's Handbook 

 of Southern Italy (1892), the correct thing for a visitor to Stromboli is 

 to make an early ascent of the cone to observe " the very curious triangular 

 shadow of the mountain cast by the rising sun upon the sea." Unfortu- 

 nately I neglected my opportunity when on the island. The shadow of 

 the mountain is also one of the sights of Etna, a dark-violet, triangular 

 shadow (Baedeker) being thrown at sunrise over the surface of West Sicily, 

 that is, on the land. I saw the shadow but imperfectly outlined, as the 

 weather was not favourable at the time of my ascent. When at Nicolosi, 

 on the south slope of Etna, I noticed at sunset a faint shadow of the 

 mountain thrown against the eastern sky. I gathered from a short con- 

 versation with Prof. Ricco, the director of the Catania Observatory, when I 

 told him of the shadow of the Hawaiian mountain, that the interest lay in 

 its projection against the sky. It is doubtless akin to the spectre of 

 the Brocken and other mountain spectres. 



Some Previous Meteorological Observations on Mauna Loa. — . . . Mr. 

 Douglas, the botanist, who was subsequently found dead in a cattle-pit on 

 Mauna Kea, -spent a day on the summit of Mauna Loa in the middle 

 of January, 1834. He mentions that a little way below the top the 

 thermometer fell at night to 19° F. The wind on the top was N.W. The 

 air at 11.20 a.m. was 33°, the hygrometer registering 0^5. He remarks 

 that the great dryness of the air was evident without the assistance of the 

 hygrometer {Hawaiian Spectator, vols. I and II, 1838-9). 



Commodore Wilkes, in vol. IV of his Narrative of the United States 

 Exploring Expedition, gives the following observations on the temperature 

 and winds on the top of Mauna Loa between Dec. 23, 1840, and Jan. 13, 

 1 841. Those on the temperature are incomplete, but they give a 

 fair idea of the prevailing conditions. The degrees are in Fahrenheit's 

 scale. 



Dec. 23, 1840 : elevation, 13,190 feet; 3 p.m., 25° F. ; strong S.W. 



gale ; night temperature, 15°. 

 ,, 24, ,, summit (13,600 feet); night minimum, 22°. 



