A Brief History of a Marine Tank. 259 



pected with greater certainty to return in full splendour in the 

 present year, and the next, when observers will probably be 

 repaid by watching for its appearance from midnight until 

 daybreak on the morning of the second Monday in November, 

 and again on the morning of the 13th of November, 1866. 



A BRIEF HISTORY OF A MARINE TANK. 



BY SHIELET HIBBEED. 



In the "Brief History of a River Tank," published in 

 February last (Intellectual Obseevee, vii., p. 38), I stated, as 

 explicitly as I could, the principal features and advantages of 

 the natural system of tank management, in order to present 

 an illustration in the case of a tank so managed, and which 

 was then, and still is, in the most perfect condition, and a 

 familiar object with a large circle of friends. In my sanctum, 

 I have a marine tank which is fitted and managed on the 

 same plan, and I propose to offer a few observations on this 

 and some other vessels which have been used for marine col- 

 lections. 



When engaged in the experiments which were the foun- 

 dation of my first written essays on the aquarium twelve years 

 ago, and subsequently of the Booh of the Aquarium, and 

 some scattered papers in periodicals, the grand difficulty 

 was to determine an exact and self-sustaining balance between 

 the various forces and influences that an aquarium brings into 

 play. Every failure then occurring was the result of attempt- 

 ing too much, and of absolutely doing too much ; and looking 

 back through all the experiences since acquired, I can say with- 

 out a blush that the original notions entertained by aquarium 

 practitioners were supremely ridiculous. Shall I ever forget 

 the waste of precious time, and strength, and money in attempts 

 to domesticate the larger forms of marine algee ? Shall I ever 

 forget the sanguine wishes that were entertained of the suc- 

 cessful cultivation of Padina pavonia, Laminaria phyllitidis, 

 Delesseria sanguinea, Ptilota yplumosa, and the lovely Griffitlisia 

 setacea, and how those hopes only faded out when years of 

 watchfulness aud wasted energy made it but too evident that 

 it was easier to dream than to do ? No, I shall never forget 

 that the one great lesson that had to be learnt, and which 

 needs to be repeated here, is that small quantities of sea water 

 enclosed in vessels in dwelling-houses, are too peculiarly cir- 

 cumstanced to be made representative of Neptune's watery 



