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On Marine Dredging^ with Notes and Observations, the result 

 of personal experience during the summers o/'1846 rtwrfl847. 

 By Robert M' Andrew, Esq., F.L.S.* 



Having been occupied dining the past and preceding summers 

 in examining, by means of the dredge, the sea-bottom adjoining our 

 coasts, in fulfilment of my duty as a member of the Dredging Com- 

 mittee of the British Association, and with the view of adding to the 

 imperfect knowledge which we possess of the invertebrate inhabi- 

 tants of the deep ; it is my intention, on the present occasion, to 

 state some of the more interesting results, with such re-marks and 

 observations as they suggest ; but without entering upon a narrative 

 of my operations during the various expeditions I have undertaken, 

 or the numerous difficulties, and even danger, with which these have 

 been attended. It may easily be imagined, that to bring up from 

 their quiet habitation the dwellers at a depth of 500 feet and up- 

 wards, while exposed to the heavy swell of the Atlantic, in northern 

 latitudes, where the weather is seldom fine and settled, can be no 

 child's play. 



My researches have been principally directed to deep water, at 

 a distance from land, in preference to inlets and sheltered situations, 

 because, in consequence of these last affording abundant results of 

 comparatively easy attainment, there are not wanting others who 

 are willing to explore them ; whereas, few or none appear to com- 

 bine the means with the inclination for the more arduous service. 

 I may be allowed to add, that any sacrifice I may have made in the 

 pursuit of knowledge has been abundantly compensated by the man- 

 ner in which my labours have been appreciated by many of the most^ 

 eminent friends of science. 



Although the dredge has long been applied to certain economical 

 purposes, such as the procuring of oysters and marine matter for 

 manure, it is only of late years that attention has been drawn to its 

 great importance as an instrument of scientific research, alike valu- 

 able to the geologist and zoologist. Its advantages consist in en- 

 abling us to become acquainted with species and forms of animal life 

 not otherwise accessible ; with the circumstances and conditions under 

 which they exist ; and in affording the only correct means of ascer- 

 taining the geographical distribution, with the vertical range, as well 

 as local habitat, of the invertebrata inhabiting the bottom of the sea ; 

 also the modifications of form occurring invariably in particular species 

 when obtained from certain depths. It will be seen in a moment 

 how the knowledge of this last fact may be applied in enabling the 

 geologist to come to a conclusion as to the depth at which some of 

 the tertiary and more recent formations have been deposited. 



* Proceedings of the Literary and Philosophical Society of Taverpool, during 

 the 36th Session, No. 14. 1848. 



