12 MR. warington's success. 



the light should pass through the surface of the water. 

 The front towards the room and the observer was 

 constructed of plate glass, the whole being set in a 

 stout framework of zinc, and cemented with what 

 is known under the name of Scott's cement, and which 

 I have found to answer for the purpose most admirably. 

 Within this tank were arranged several large pieces 

 of rock-work, thrown into an arched form, and other 

 fragments were cemented in places against the slate 

 at the back and ends, and at parts along the water- 

 line, so that the creatures could hide themselves at 

 pleasure ; a short beach of pebbles was also construct- 

 ed in order that shallow water could be resorted to if 

 desired. The whole tank was covered with a light glass 

 shade to keep out the dust, and retard evaporation. 



"With the sea water obtained in January, 1852, 

 I have been working without cessation up to the 

 present time, agitating and aerating when it became 

 foul during the unsuccessful experiments on the sea- 

 weeds, but since then it has been rarely ever disturbed ; 

 the loss which takes place from evaporation being 

 made up, as before stated, with rain or distilled water." 



My own experiments with marine animals and 

 plants were commenced about the same time as Mr. ff< 

 Warington's, namely, at the end of January, 1852. I 

 was not aware till long afterwards that either that 

 gentleman or any one else had proposed to effect such 

 an object, which had been occupying my mind for 

 some time. My success, which was less perfect than 

 Mr. Warington's, I published in the "Annals of 

 Natural History" for October, 1852, and subsequently, 

 in my " Eambles on the Devonshire Coast." Travel- 



