MISCELLANY. 



633 



Africa. In the island of Bali, near Java, a 

 woman who is so unfortunate as to bear 

 twins is obliged, along with her husband, 

 to live for a month at the sea-shore or 

 among the tombs, until she is purified. The 

 Khasias of Hindostan consider that to have 

 twins assimilates the mother to the lower 

 animals, and one of them is frequently put 

 to death. An exactly similar belief pre- 

 vails among some of the native tribes of 

 Vancouver Island, Among the Ainos, one 

 of the twins is always killed, and in Arebo, 

 in Guinea, both the twins and the mother 

 are put to death. 



Father Secchi on Solar Spots. In sum- 

 ming up the results of his observations on 

 solar prominences and spots from April, 

 1871, the Roman astronomer, Father Secchi, 

 states that since that date there has been a 

 very marked diminution both in the num- 

 ber of groups of sun-spots and in their 

 area a result of the eleven-year period, the 

 maximum having occurred about 1871. But 

 he has observed the same diminution in the 

 number of prominences: in 1871 the daily 

 average was about fifteen, while now it is six 

 or seven. In the same period the number of 

 groups of sun-spots in each rotation has de- 

 creased from about twenty-five to eight, and 

 the mean area has diminished to about one- 

 fifth. Further, the prominences are now very 

 rare near the poles. Secchi further remarks 

 on the discordance between his results of 

 1852, showing a difference of temperature 

 between the solar equator and poles, and 

 those of Prof. Langley, and infers that there 

 has been a change in the sun in this respect, 

 consequent on the decrease of solar activ- 

 ity. He objects to Langley's method of 

 moving his thermopile to different parts of 

 the image instead of moving the telescope 

 so as to bring the points of the image in 

 succession on the thermopile, and thus to 

 avoid differences of inclination to the axis 

 of the lenses. 



Prcf. Loomis on the Storms of the United 

 States> This eminent meteorologist pre- 

 sents, in the July number of the American 

 Journal of Science^ his third paper on 

 storms, founded on the weather-maps of 

 the Signal-Service. He is now able to 

 confirm what was stated in his previous 



papers in regard to the general progress, 

 direction, and barometric phenomena of 

 storms in the United States. These papers 

 of Prof Loomis are admirable in method, 

 and of very great value. The general di- 

 rection of the storms which traverse the 

 United States is found to be a little north 

 of east, but varies somewhat with the sea- 

 sons. Thus, July storms are most southerly 

 in their direction, being a little south of east, 

 those of February being most northerly. 

 Rarely, storms move for a time northward 

 or southward. 



By direction of a storm is meant the 

 movement over the country of the whole 

 storm, not the direction of the winds, and 

 its progress varies greatly in rapidity. The 

 average velocity during the past three years 

 has been 26 miles per hour, the storms of 

 August being slowest, those of February 

 and March being most rapid. The storm 

 of February 22, 1874, moved at the tremen- 

 dous rate of 53.3 miles an hour, or 1,280 

 miles in a day. 



It is also shown that the progress of 

 storms is not uniform throughout the day, 

 but has a uniform daily variation. The 

 velocity is greater by 25 per cent, from 

 4.35 p. M. to 11 p. M. than during other 

 portions of the day, and this is constant 

 during each month of the year. The 

 greatest velocity occurs at about 7 p. m. 

 without apparent relation to the wind's ve- 

 locity, or absolute temperature. " But," the 

 professor observes, " it is the time when the 

 temperature of the day is declining most 

 rapidly." Now, this change of temperature 

 has direct relation to those conditions which 

 cause precipitation and extend the rain-area. 

 By reference to a former paper of Prof. 

 Loomis it will be seen that condensation in 

 front of the storm-centre is one means by 

 which a storm progresses. It is continually 

 making up in its front where the air is va- 

 por-laden, not in its rear where the air has 

 been deprived of its vapor. 



It will hardly admit of question that 

 the velocity of a storm's forward motion is 

 usually accompanied by an extension of the 

 rain area in the direction in which the storm 

 progresses. The average extent of this 

 area in front of the storm-centre during 

 three years is found to be 542 miles. Now, 

 if this be increased 100 miles, the velocity 



