APPENDIX IV. 

 PATENT CARBONIZED HATCHING TROUGHS. 



WHEN the first efforts at trout breeding were made 

 in this country, wooden troughs were used for hatch- 

 ing the eggs. It was soon found that the fungus which 

 grew on wood when under water was exceedingly destruc- 

 tive to the eggs. Indeed, of all the dangers to which the 

 eggs were exposed, fungus proved to be the worst. It de- 

 stroyed them by thousands and hundreds of thousands, and 

 those which it did not actually kill it rendered worthless by 

 exhausting their vitality. It therefore became indispensa- 

 ble to abandon the use of wood for hatching trout eggs. 

 The great want was, then, to find something which, by 

 being inexpensive, accessible, and at the same time safe 

 from fungus, would supply the place of the old wooden 

 troughs. The emergency brought out various materials, 

 soapstone, slate, pottery, glass, metallic screens and pans, 

 wood lined with glass, and other things, all of which were 

 tried and found to be either inadequate or expensive, and 

 the want of a cheap and safe material was still unsup- 

 plied. 



It was at this time, after many useless experiments, and 

 the loss of many thousands of eggs, that the writer hit 

 upon charred or carbonized wood. This was tried, and 

 found to answer the purpose beyond all expectations. 

 Nothing could be conceived more perfect in its adaptabil- 

 ity. The problem was solved. In carbonized wood was 

 found an inexpensive, accessible, and perfectly effective 

 material for hatching fish eggs, without danger from fun- 



