76 



Scientific Notices — Miscellaneotis. 



[Jan. 



1. The almost universal remark that the Baltic has become 

 shallower in the ordinary sailing tracts, is admitted by the pilots 

 to be not destitute of foundation, but they are of opinion that 

 this alteration is in general most perceptible in situations 

 exposed to the afflux ofdriftsand, loose pebbles, or sea-weed, or 

 where the bottom consists of rock, A similar observation has 

 been made in the proximity of the larger towns and fishing sta- 

 tions ; for example, according to the chart drawn up in 1771, 

 the mean depth of the sea opposite the harbour of Landskrona 

 was six fathoms; in 1817, it was scarcely five fathoms. 



2. Between the numerous islets which are scattered along the 

 coast of Sweden from Haarparanda to the boundaries of Nor- 

 way, there are sailing tracts where, '60 or 90 years ago, accord- 

 ing to the testimony of the oldest and most experienced pilots, 

 the sea admitted ships having a draught of 10 feet, although at 

 present they are impassable to vessels whose draught exceeds 

 two or three feet: at the same time it does not appear that older 

 tracts, in the immediate vicinity of these, have become sensibly 

 shallower. 



3. It is asserted also by the pilots, that along the whole coast 

 of Bahusia, the sailing tracts where the bottom consists of rock, 

 undergo a sensible diminution of their depth every 10 years. 

 Many other parts of the Baltic might be mentioned, in which a 

 similar alteration has been taken notice of. 



M.. C. P. Hallstrom, in a valuable appendix to M. Bruncona's 

 memoir, gives the following table of the corresponding diminu- 

 tion which has been observed in the water of the Gidf of 

 Bothnia. 



