PUBLIC AQUARIUMS IN EUROPE. 



17 



sacrificed on this account, for the concreted bottom of the tank 

 may be made to slope downward from the base of the glass plate 

 till the needed depth is reached. Nor does the similarity in the 

 various aquariums extend only to the corridor to which the gen- 

 eral visitor is admitted. In their internal arrangements an even 

 more strikingly similar ground plan is found to prevail. In all 

 cases the attempt has been made to keep from the mind of the 

 visitor the idea that water pipes, pumping engines, and blouse- 

 wearing attendants none of which withal are oppressively tidy 

 are necessary to the well-being of the tanks. And it is for this 

 reason especially that the region behind the tanks is usually 

 kept from profane eyes. Dark passageways lead to it, shielded 



Amsterdam Aquarium Service of the Basins. 



by hidden doors, and one who enters, coming from the dusky cor- 

 ridor, is at first blinded with a flood of light. Above him is the 

 glass roofing of a conservatory, and sunshine is pouring down 

 upon the rock work of the tanks, thence to be reflected into the 

 public hall. At his feet extends a concreted pathway ; on either 

 side are the tanks, or more strictly rock-lined pools, at whose 

 farther ends can be seen the glass plates through which, in the 

 corridor, the visitors are gazing. Above and around are serpent- 

 like pipes, stretching at full length, abruptly coiling as they dip 

 to the water surface or pass downward below the floor, a con- 

 fusing maze, bubbling and hissing with steaming water. The 

 system in the management of the water supply becomes, how- 

 ever, clearly understood when the mystery of strangeness has 

 passed away. It has merely to conform to the hygienic law of its 



