1825.] Mr. Mill on changing the Residence of Pishes. 379 



In 100 parts. 



1 atom of bitartrate of potash 180 .... 49*58 



3 atoms of protoxide of antimony (52 x 3) . . . . 156 .... 42'97 

 3 atoms of water (9x3) 27 7-45 



363 100-00 



■ According to Dr. Thomson, as already quoted, the atomic 

 Weight of tartarized antimony is 354, differing from the above 

 by 1 atom less of water. 



Article VII. 

 On changing the Residence of Fishes. By Nicliolas Mill, Esq. 

 (To the Editors of the Annals of Philosophy/.) 

 GENTLEMEN, 



In reading Dr. Mac Culloch's paper on '• Changing the 

 Residence of certain Fishes," in the 34th number of the Quar- 

 terly Journal, I was impressed with the importance of the sub- 

 ject to society, and I conceive that any facts which can be col- 

 lected in corroboration of his statements, cannot fail to be 

 interesting and useful. I therefore take the liberty to forward 

 you some facts which have come under my observation respect- 

 ing the habits of the salmon, and the likelihood of its being 

 domesticated (if I may use the expression) in fresh water lakes 

 and ponds. The salmon has many peculiarities in its history 

 and mode of living which are common to most of the finny tribe 

 that are inhabitants alike of fresh and salt water, and some 

 which others have not. The salmon during certain months of 

 the year is an inhabitant of fresh water rivers and lakes that 

 communicate with the sea, and apparently for the sole purpose 

 of depositing its ova or spawn. It then again betakes itself to 

 the sea to recruit its strength and vigour, but, unlike other migra- 

 tory fishes, its retreat cannot be traced; for it is a singular fact, 

 that salmon have never been taken or seen in the salt water far 

 from the mouth of some river, and there only at certain seasons 

 of the year. The herring, the pilchard, the mullet, and the 

 mackerel, may be followed from one sea to another, and from 

 one creek to another, but not so with the salmon whose hiding- 

 place is a mystery, yet to be solved by naturalists. The general 

 opinion entertained upon this subject is, that they do not wan- 

 der far from the shores of the fresh water rivers they frequent, 

 from the well known fact that the same salmon will always return 

 to the same river to deposit its spawn ; and if they do migrate to 

 the northern seas (which some naturalists maintain where they 

 are found in abundance, but always, it must be remembered, in 



