BULLETIN OF THE UNITED STATES FISH COMMISSION. 291 



Bay and bringing thein to Wood's Holl, where they were kept supplied 

 Avith water running from a faucet for several days. At the end of that 

 time the soft parts had shrunken to a remarkable degree and acquired 

 a toughness and leathery consistency in marked contrast with that ob- 

 served in the animals before the experiment was tried. These effects 

 are produced, as is well known, by osmotic action. 



STORAGE FLOATS. 



An ingenious system of floats, which are raised and lowered by means 

 of windlasses, are used in this work by Mr. Conger, of Franklin City, 

 Md. This apparatus is a great convenience in storing oysters tempo- 

 rarily near the oyster houses, where they are packed for market. The 

 floats are 20 to 25 feet long and 7 or 8 feet wide, with a bottom made of 

 strong slats. The windlasses are supported on the tops of four piles 

 driven into the mud in two pairs, one at either end of the float. 



ECONOMICAL SIGNIFICANCE OF THE STOCKTON EXPERIMENT. 



The success in rearing oysters from the eggs, as practiced at Stock- 

 ton the past summer, admits of no doubt whatever ; inasmuch as there 

 could be no question as to the identity of the eggs from which the spat 

 which caught ou the collectors was derived. No other ova could by 

 any means have gained access to the inclosure, so as to vitiate our re- 

 sults. But this success I do not esteem of as much value as the facts 

 of collateral importance which it has substantiated. These are the fol- 

 lowing: 



First. It has proved that oysters may be grown in inclosed ponds. 



Secondly. It has proved that an abundance of food will generate in 

 such inclosures. 



Thirdly. It has proved that we can depend upon the tide to renew 

 the waters of such ponds. 



Fourthly. It has been shown that the cost of digging out ponds on an 

 extensive scale would be a comparatively inexpensive undertaking, be- 

 cause no digging is required except such as can be done with a spade. 

 The nature of the salt marsh is such that it can be cut into any shape 

 desired ; the black muck of the marsh being interpenetrated with great 

 numbers of roots and decayed fibers of vegetable matter which render 

 it tough, so that it can be cut out in solid blocks. About the depth of 

 what would be taken by three superimposed spadesfull is a sufficient 

 excavation for the purposes of pond culture in many places. There are 

 thousands of acres along the eastern coast of the United States of salt 

 marsh lauds which are available for pond culture, besides the ground 

 already occupied off-shore ; so that the development of the industry 

 seems to be practically unlimited. Wherever the water is fresh enough 

 to grow oysters, and where such marsh lands also exist, the construction 

 of ponds for oyster culture is feasible ou just as grand a scale as is now 

 practiced on some parts of the coast of France. 



