2/4 Transactions of the [Sess. 



these cases the fall from the atmosphere had taken place before the 

 observations were made ; and no evidence existed that the appear- 

 ances were atmospheric, and not terrestrial. On the other hand, 

 on several occasions the atmosphere had previously been observed 

 to be filled with red-dust particles before the red rain fell — for ex- 

 ample, at Bag-dad in 929, and at Kome in 1222. 



But it v^as not till the beginning of the seventeenth century that 

 true interpretations began to be forthcoming. A shower of blood- 

 rain occurred at Aix in 1608, which greatly alarmed the people, 

 whose frenzy was still further increased by the clergy. Peiresc, 

 however, soon offered a simple explanation. He had observed that 

 Butterflies were then very abundant, and that after the escape of 

 the imago from the pupa state a droplet of red juice remained, and 

 produced a red speck. These specks were found to occur in places 

 accessible to Butterflies, but where no rain had fallen, and inquiry 

 revealed that occurrences reported earlier might be similarly inter- 

 preted. The explanation became generally accepted ; and for the 

 first time insects were looked upon as possessing a new and pecu- 

 liar property. 



Swammerdam, while journeying in France about the middle of 

 the seventeenth century, also observed, and was alai'med at, certain 

 blood-coloured water which he met with. He examined it, how- 

 ever, and found the cause to be the presence of a small Water-flea 

 [Daphnia pulex). Schuyl ^ similarly explained a similar phenome- 

 non which had excited the inhabitants of Leyden. 



The observations thus instituted during the seventeenth century 

 were continued with still greater zeal during the eighteenth. In 

 1700, Eomberg directed attention to the reddening produced by the 

 cases of Bees in the vicinity of bee -hives; and in 1711, Hilde- 

 brandt, from observations made in Sweden, corroborated the influ- 

 ence exerted by insects. Westphal, in 1716, observed red spots 

 on plant-leaves in the vicinity of Delitzsch and Wittenberg ; and 

 not being able to regard these as due to insect products, he laid 

 himself open to the charge of being occupied with alchemist ex- 

 perimental theories, by asserting that the appearance was the re- 

 sult of dew, coloured red by the presence of sulphurous matter. 



In 1746, a phenomenon on a larger scale, and one demanding a 

 new explanation, was recorded by Gonsag in California. He believed 

 that springs occurred in the sea, as at flood-tide the water, for an 

 extent of half a mile, was of a bluish-red hue. A chemical action 

 was here believed to be taking place between the spring and sea 

 water. Linnaeus attributed blood-rain to the presence of a small 

 animalcule, Monoculus pulex, w^hich was similar to the Cyclops 

 qiiadricornis found in similar conditions in Sweden by Agardh. 



So early as 1646, a chemical examination of red rain had been 



1 ' Bibel der Natur,' p. 40. 



