224 Appendix. 



ity was 2.07. Silica, alumina, lime and iron were its chief con- 

 stituents.* 



It was not until 1846 that a general examination of these 

 rains was made, and their origin found by following them into 

 space. On May i6th of that year, an earthy rain fouled the 

 the waters at Siam. In the autumn of the same year, there was 

 a similar fall, accompanied by very disastrous huricanes, which 

 occurred alternately, or nearly so, in such a manner as to be 

 only explicable by some great disturbance in the system of trade 

 winds. Cyclones swept over the Atlantic, amidst fearful squalls, 

 whirlwinds and hail-storms. A tempest also prevailed in France, 

 Italy and Constantinople. The winds were of sufficient inten- 

 sity to detach a stratum of land in places where the surface was 

 sandy. This earth carried into the air was certain to be depos- 

 ited somewhere. This took place in the south of France. 

 Ehrenberg, who analyzed samples of this earth, found in them 

 seventy-three organic forms, some of which were peculiar to 

 South America, and concluded that its origin was in the new 

 world. The interval of time between their leaving America, 

 Oct. 13th, and their arrival in France, Oct. 17th, was about four 

 days, which gives a speed of 18^ yards per second. The last 

 remarkable shower of red rain, according to the author above 

 quoted, was that of Feb. 13th, 1870. 



On Feb. 7th, a great barometrical depression occurred in 

 England. On the 9th, it had reached the Mediteranean ; on the 

 loth, Sicily. This fall of barometer was accompanied by a vio- 

 lent tempest. On the nth and 12th, the weather was calmer 

 and the barometer reading increased again, the cyclone rag- 

 ing over the desert of Sahara. From Africa, the hurricane and 

 cyclone again made its way back to Europe, accompanied by the 

 sand swept up from the Sahara. On the the 13th, a reddish rain 

 fell at Rome, which, upon investigation, was found to be sand. 



The list of cases of this kind might be very much enlarged 

 upon. Over twenty of these, with dates and places of occur- 



*Flainmariaii, p. 455. 



