DESCRIPTION OF MARINE HATCHERY AT DUNBAR, SCOTLAND. 261 



at every tide a fresh supply of water may be admitted if desired. Both pipes open 

 on the inner side into a long, vertical water-tight wooden box, which fits against the 

 concrete wall, and is open above so that the valve may be controlled. Large filtering 

 frames are fitted into apertures in this box by india-rubber joints, so that practically 

 every drop of water entering the pond may be passed through them — a very useful 

 provision in stormy weather. 



At the end opposite to the concrete wall is a stone-work platform continuous with 

 the harbor quay, and a door is let into the wall, at this part of which entrance to 

 the pond is obtained. The length of the pond is 42 feet, the average breadth about 20 

 feet, and the depth of water at high tide about 9 feet; it can therefore contain nearly 

 50,000 gallons of water — all of which, as has been explained, filters itself as it passes 

 in. The bottom is laid with concrete, and when fish are present this is covered with 

 a layer of clean sand. The purpose of the tidal pond is twofold: (1) it serves as a 

 storage place for the spawners, in which they may be collected before the spawning 

 season, and (2) as a reservoir of pure filtered water which may be pumped up to the 

 hatching house during the prevalence of storms, when the water outside may become 

 somewhat turbid in certain winds. As the tide rises the water pours in by the upper 

 pipe and passes through the filtering apparatus into the pond; when the tide falls, 

 the valve closes automatically and prevents the escape of the water. 



The pumping apparatus consists of two Worthington brass-lined, direct-acting 

 steam pumps, each capable of throwing over 3,000 gallons per hour. The boiler is of 

 the best locomotive type, made of steel, by Robey & Co., Lincoln, and of 8 horse 

 power. The pump house is placed between the hatchery and spawning pond on the 

 one hand, and the harbor and tidal pond on the other hand. It is 24 feet long by 18 

 feet in breadth. The floor is of concrete, and a partition separates the boiler from the 

 pumps. Built against the boiler compartment is the coal house, which can accommo- 

 date about 12 tons of coal. The pumps are so fitted up that one may pump from the 

 entrance to the harbor, and the other from the tidal pond, or one or both may pump 

 from the harbor and the pond at the same time. The suction pipes are 2£ inches in 

 diameter/and made of the best galvanized iron; they are supplied with foot-valves 

 and roses. The supply pipe to the spawning pond and hatchery is of the same 

 diameter and material. At the side of the spawning pond a branch is given off to 

 the filtering-gallery, and this branch on entering the gallery bifurcates to supply each 

 of the two series of filtering-boxes. Cocks are placed so that the volume of water 

 entering the spawning-pond or the filtering gallery can be easily regulated. The 

 Worthington pumps have worked very smoothly, without any noise, and have given 

 satisfaction. 



There is a special feature in connection with the working of this hatchery to which 

 attention may be drawn. At the Norwegian establishment and, 1 understand, at 

 others, the pumps are kept working during the night as well as in the day, so that a 

 constant supply of water may be obtained for the spawning pond and the hatching 

 boxes; this, of course, necessitates extra staff and expense. At the Dunbar hatchery, 

 however, the night work is dispensed with, water from the spawning ponds being used 

 for the hatching boxes and the waterwheel, by means of the three pipes, previously 

 referred to, which pass through the wall of the pond. These pipes are fitted on the 

 inner end, which projects into the pond, with large haircloth roses or filters, which 

 prevent any eggs passing out with the water. One of these is connected in the gallery 



