104 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



being- laid in tlie solution for 3 days, when tbey are taken out and dried. 

 Generally the tanning is repeated twice; and there are therefore in all 

 3 tannings. The old bark in the vat is stirred each time and new bark 

 is added until the solution regains its original strength. Occasionally 

 fine lime (1 part to 100 parts water) is used for fixing the solution. In 

 this solution, which should be prepared the day beforehand, the nets 

 should be dipped. The color will show as soon as the net is put into 

 salt water. After every fishing the tanning should be repeated once ; 

 and care should be taken, first to clean the net, and especially to re- 

 move all fatty substances. As regards the treatment of the nets dur- 

 ing the fisheries, the same rules apply as are given above. 



METHODS USED IN FAGERHEIM'S NET FACTORY, BERGEN, NORWAY. 



Tanning nets. — For every 132 pounds of nets 14^- pounds of catechu 

 are dissolved in 38 quarts of boiling water. The solution is poured 

 over the nets, and they remain in it until it has grown cold. The tan- 

 ning is repeated three times, the nets being dried after each tanning, 

 and a fresh solution is used every time. An experiment has been made 

 in using fine lime with birch bark. It gives the net a purplish color. 



Galvanizing nets. — A solution of § pound of copj)er vitriol and 120 

 quarts of cold water is used, in which the nets are laid for 24 hours. 

 To make the solution requires 24 hours. For 3G pounds of nets 1 pound 

 of the vitriol is used. 



35.— SALiITIOIV FISnEKIES OF IIAJLI^AIVD, SWEDEIV, ESPECIAIililT IIV 



THE RIVER VISKAIV.* 



By FILIP TKYBOM. 



From various sources I have obtained data relative to the salmon 

 fisheries in the river Viskan during thirty-seven years ending with 1884. 

 From these data it appears that the smallest average weight of the 

 salmon per month was found most frequently (in eighteen years) in 

 August, and in eight years each in September and July, twice in Octo- 

 ber, and once in April. It should be noted that in more than one-half 

 of the years when the smallest monthly average weight was found in 

 August, the fisheries came to an end in that month. This api)lies not 

 only to the Viskan, but to all the rivers of ITalland. The salmon had 

 the largest average weight in July in eighteen yefirs, in May in nine 

 years, in Aj^ril in five, in March in three, and in February and August 

 in one year each. In the rivers Nissan and Lagan the average weight 

 in 1884 was largest in June ; while in the river Rhine the largest salmon 

 are caught during the period from December to April. 



* " Larfinket i aarne, sarskiU del i Vislcan." From " Om Fislcerieriia i IlaUand 18H4," 

 Liiiul, Sweden, 1885. Translated from the Swedish by Herman Jacobsox. 



