FRAGMENTS OF SCIENCE. 



717 



mas, and as far as the Bermudas, 10.11 

 miles ; from the Bermudas to the Azores, 

 6.42 miles. The mean speed for the North 

 Atlantic was 4.48 miles. The figures are un- 

 der rather than above the truth. 



Winds of the Sahara. — Some interesting 

 meteorological observations, made in the Sa- 

 hara during eight excursions between 1883 

 and 1896, have been published by M. F. 

 Foureau. The most frequent winds are 

 those from the northwest and the southeast. 

 Every evening the wind goes down with the 

 sun, or goes to bed, as the Chaambe express 

 it; except the northeast wind, which the 

 Arabs call el childne, or the devil, because 

 it blows all night. Another wind, called the 

 chihifhi, has been mentioned by all travelers, 

 and is the subject of numerous legends. It 

 is a warm wind from the southwest, charged 

 with electricity, and often carrying fine sand 

 and darkening the atmosphere. The com- 

 passes are much disturbed by it, because, 

 it has been suggested, of a special condition 

 produced upon thin glass covers by the fric- 

 tion caused by the rubbing of the fine wind- 

 carried sand upon them ; but it has been ob- 

 served that the spare compasses show the 

 same disturbed condition as soon as they are 

 taken out of their boxes. The disturbance 

 ceases when the glasses are moistened, and 

 does not appear again till they have dried. 

 Several hailstorms were noticed, the hail- 

 stones being usually about as large as peas, 

 but larger in the heavier storms. M. Fou- 

 reau, not having gone as far as the central 

 heights, observed no snow in the Sahara, but 

 was informed that snow falls in the winter on 

 the tops of the Tassili des Azcljcr, about five 

 thousand feet above the sea. Similar obser- 

 vations have been made by other travelers, 

 and falls of temperature to about 21° F. have 

 been noticed. Very curious mirage phenom- 

 ena were sometimes observed. Observations 

 of fulgurites, or instances in which the sand 

 had been vitrified by lightning strokes, were 

 not infrequent. 



Evolution of Pleasure Gardens. — A les- 

 son in the evolution of pleasure resorts is 

 suggested in a book by Mr. Warwick 

 Wroth on the London pleasure gardens. The 

 history of these places has in some cases 

 a strong family resemblance. They usually 



began as tea gardens, with a bowling green, 

 tea and coffee, hot loaves, and milk " fresh 

 from the cow," as their chief attractions. 

 If the business prospered, other amusements 

 were added, such as music and dancing, with 

 perhaps the exhibition of a giant or a fat 

 woman. Equestrian performances were given 

 in the more important gardens. The mana- 

 ger of one of them kept on the grounds a 

 fine collection of rattlesnakes, one having 

 nineteen rattles and " seven young ones." 

 " Sixteen hundred visitors were present at 

 another one day in August, 1744, to hear 

 honest 'Jo Baker' beat a trevally on his 

 side-drum as he did before the great Duke 

 of Marlborough at the bloody battle of Mal- 

 plaquet. It was not unusual, moreover, for 

 the owner of a successful tavern to discover 

 on his premises a mineral spring, of which a 

 favorable analysis was easily obtained" — 

 although the spring might be really a bad 

 one. The Spa of Hampstead Wells enjoyed 

 a delightfully pure and invigorating air on 

 the open heath, and had a tavern with coffee 

 rooms, a bowling green, raffling shops, and a 

 chapel, which offered visitors an advantage 

 possessed by no other gardens in London, as 

 a clergyman was always in attendance, and 

 a couple on presenting a license could be 

 married at once on the payment of five shil- 

 lings. Mr. Wroth suggests that the license 

 was sometimes dispensed with, and the fee, 

 moreover, was remitted if the wedded pair 

 gave a dinner in the gardens. 



A Library of Astronomical Photographs. 



— The appointment of Mrs. M. P. Fleming as 

 curator of astronomical photographs in the 

 Harvard Observatory is noteworthy because 

 hers is the first woman's name to be placed 

 along with the officers in the university cat- 

 alogue. It is more so as a recognition of 

 Mrs. Fleming's proved abilities in certain 

 lines of astronomical work. The astrophoto- 

 graphic building is not used for the taking 

 of photographs, but as a peculiar kind of 

 library where the plates secured by the as- 

 tronomers at Cambridge and Arequipa are 

 preserved, arranged, and catalogued, as is 

 done with books. The duties of the curator 

 are like those of a librarian. But instead of 

 books, of which many copies exist, each of 

 the treasures in the photographic collection 

 is unique and can not be duplicated. Prints 



