of a Lake near Lulot'tn, in Soufh Prussia. 24,5 



^nubt from the observations having been made at diflerent 

 •timts. 



It may readily be believed that superstition, as usual, con' 

 verted this natural plisnomenon into a wonderful prodigy, 

 which was considered as the consequence of a shower of 

 blood, and the forerunner of various misfortunes. 



To the enlightened philosopher, however, such phaeno- 

 mena are of importance, as tlicy afford him means of ex- 

 plaining, on true principles, what few men of science have 

 made an object of their research. 



It needs, therefore, excite no wonder that different opi- 

 nions have been entertained in regard to the nature and 

 cause of this phajnomentm. Some ascribed it to niinera,! 

 substances, and thence deduced proofs of the existence of 

 veins of ore concealed in the neighbourhood. Others con- 

 ceived that it Jiad some connection with the earthquake 

 which had a little before been experienced in several parts 

 of Silesia and Bohemia. But, by the help of chemistry, 

 this phaenomenon has been found susceptible of another 

 explanation much simpler. 



Various authors, both antient and modern, speak of 

 water being coloured and altered in its appearance. \\ e 

 are told by Pliny* thai the water of the lakes near Babylon 

 had a red colour for eleven davs iu sui^inqier, and that the 

 Borysthenes, now called the Diiieper, was in summer of a 

 blue colour. In \G63 Mr. Smithf found the water of the. 

 Mediterranean to be of a sky blue colour, and when the 

 sun shone upon it this colour was chauged to red or purple. 

 The missionary Ferdinand Consag J, in the yeaf 1746, ob- 

 served in the open sea, near California, that the water for 

 the extent of half a mile was of a bluish red colour. Navi- 

 gators liave often seen the water at the mouth of the river 

 Plata, on the coast of South America, of a blood red 

 colour. Schooten found the water at Cape Desire coloured 

 red, in consequence of a sea unicorn [Munodon Monoccroi). 

 having lost its horn. 



Water is sometimes coloured red, not in reality, but ap- 

 parently by aquatic insects, which at certain seasons cover 

 the surface of ditches and ponds. 



The present case, however, is different. The coloured 

 water of the Jake near Lubolin, a consideral)!e quantity ot 

 ivhich was sent to lierlin for chemical examination, excited 

 great attention when lirst seen, by its agreeable change-, 



* Jliit. Na'. liii. xxxi. rail. -lo. t Acta KriiHit. 1701;. 



J ll.it. lie Californic, torn. iii. Paris 1767. 



C) 3 ablencss 



