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resulted from persons not understanding just the conditions which were 

 necessary to ensure success. 



Mr. T. C. White said that as an old keeper of a marine aquarium he 

 had to thank Mr. Waddington for bringing this subject forward. He had 

 himself read a paper on the same subject before the Club some years ago, 

 and had seen no reasons since for altering the opinions he then stated. He 

 kept up his aquarium for 17 years, and did not change the water once during 

 that period. He could strongly recommend anyone to set up one for himself, 

 and if it was kept in good condition a number of creatures would be born in 

 it which would afford an endless variety of interesting studies. If it was 

 possible to obtain them it was an excellent plan to obtain some old oyster 

 shells such as were dredged up from a considerable depth and had a number 

 of holes in them ; these perforations were excellent traps for organisms of 

 various kinds which would in a short time develop and add greatly to the 

 interest of the aquarium. With regard to diluting the water, this was a 

 very important point and required great care. He used to supply the loss 

 from evaporation by pouring in cold boiled water, for fear of adding too much 

 lime ; distilled water was, of course, the proper thing, but he found that 

 cold boiled water answered the purpose very well. It should be poured in 

 very gently to prevent disturbance and to avoid altering the specific gravity 

 too suddenly. He found it a good plan to take out about a quarter of the 

 water so as to dilute the fresh water before adding it to the aquarium. The 

 scum which formed on the surface might be easily removed with a strip of 

 blotting paper. He quite agreed with Mr. Waddington as to the reason why 

 so many people experienced disappointment in trying to preserve a marine 

 gathering for home examination ; they were in too much of a hurry to put 

 their specimens into water which was unfit to receive them, because it was 

 not at first sufficiently rich in oxygen to afford them support. They all 

 knew how persons at the seaside put things into a glass, and how they found 

 them all go bad in a day or two, whereas if they had prepared the water first 

 it would have been a success. That was a hint to gatherers which they 

 would find useful. He did not pretend to have attained the same success 

 as Mr. Waddington, but he had kept Crassicomis, Anthia, &c, and he could 

 certainly recommend all the Members to take up " Marine Aquaria," the 

 possession of which added a new joy to the life of any microscopist. 



Mr. Goodwin asked if Mr. White ever tried the plan of obtaining any of 

 the washings of marine fish or of marine shells ? He thought it might be a 

 good way to get minute organisms. 



Mr. T. C. White said that some time ago when he was keeping a marine 

 aquarium he got some of the Pecten shells and obtained from them a quantity 

 of ova and other things. 



The President was sure they had all listened to the paper and to the 

 remarks which followed it with extreme interest. 



The thanks of the meeting were then voted to Mr. Waddington for his 

 paper. 



Mr. T. F. Smith read his paper " On Arachnoidiscus as a test for high 

 power objectives." 



