170 COLOURS OF THE SEA. 



Some hues of the ocean are traceable to animal- 

 cules. Dr. Poppig, in his " Voyage to Chili," says, 

 " From the topmast the sea appeared, as far as the 

 eye could reach, of a dark red colour, and this in a 

 streak the breadth of which was estimated at six 

 English miles. As we sailed slowly along, we found 

 that the colour changed into brilliant purple, so that 

 even the foam, which is seen at the stern of a ship 

 under sail, was of a rose colour. The sight was 

 very striking, because this purple streak was marked 

 by a very distinct line from the blue waters of the 

 sea, a circumstance which we the more easily ob- 

 served, because our course lay directly through the 

 midst of this streak, which extended from south- 

 east to north-west. The water, taken up in a 

 bucket, appeared indeed quite transparent, but a 

 faint purple tinge was perceptible when a few drops 

 were placed upon a piece of white china, and moved 

 rapidly backwards and forwards in the sunshine. A 

 moderate magnifying glass showed these little red 

 dots, which only with great attention could be dis- 

 cerned with the naked eye, consisting of infusoria, 

 which were of a spherical form, entirely destitute of 



all external organs of motion We sailed for 



four hours at a mean rate of six English miles an 

 hour, through this streak, which was seven miles 

 broad, before we reached the end of it ; and its super- 

 ficies must therefore have been about a hundred 

 and sixty-eight English square miles. If we add 

 that these animals may have been equally dis- 



