14 THE AQUARIAN NATURALIST. 



on the 21st of April. The following day I poured off 

 about half of the quantity made (filtering it through 

 a sponge in a glass-funnel) into a confectioner's show- 

 glass. I then put in a bottom of small shore pebbles, 

 well- washed in fresh water, and one or two fragments 

 of stone with fronds of green sea- weed (Ulva latissima] 

 growing thereon. I would not at once venture upon 

 the admission of animals, as I wished the water to be 

 first somewhat impregnated with the scattered spores 

 of the Ulva, and I thought that if any subtle elements 

 were thrown off from growing vegetables, the water 

 should have the advantage of it before the introduc- 

 tion of animal life. This, too, is the order of Nature 

 plants first, then animals. 



" A coating of green spores was soon deposited on 

 the sides of the glass, and bubbles of oxygen were 

 copiously thrown off every day, under the excitement 

 of the sun's light. After a week, specimens were in- 

 troduced into the vivarium thus prepared for their 

 reception. These grew and flourished from day to 

 day, manifesting the highest health and vigour : the 

 plants, including one or two red sea-weeds that were 

 put in with the animals, looked well, and the water 

 continued brilliantly crystalline. In short, the experi- 

 ment succeeded perfectly, and we may now employ 

 with confidence the artificial element when real sea- 

 water cannot readily be procured/' 



The proportions of saline materials recommended 

 by Mr. Warington for the formation of artificial sea- 

 water are somewhat different from those employed 

 by Mr. Gosse, and correspond more accurately with 

 Dr. Schweitzer's analysis. 



