JAN. — MAR. 1857.] voijage from England to Madras. 149 
here and there brighter specks intermixecl. This appearance we af- 
terwards ascertained was partly, if not wholly, caused by multitudes 
of phosphorescent marine animals, chiefly Crustacea and many 
of them, microscopic. By the 7th April in Lat. 
31-11 N. Long. 17-28 W. the wind having abat- 
ed, many Physalias harbingers of calm weather, 
floated past, catching the wind by means of their 
purple crests. Meanwhile we proceeded to prepare 
our towingapparatus which was simply a bag made 
of double mosquito gauze of a conical shape as in 
the accoitipanying wood-cut Fig. I. It was 1| foot 
long, t^e widest end open and made to fit a circu- 
lar iron hoop of 8 or 9 inches in diameter, to 
this was attached 15 or 20 fathoms of cord the 
size of a ship's log line. This form we found well 
adapted to use in light winds, but in anything of 
a breeze it too quickly filled with water which 
as rapidly regurgitated and carried with it all the 
contents of the net. To remedy this defect we con- 
structed another net of the form shown in the annexed wood-cut 
Fig. II. which retained its contents better than the 
other in windy weather. Macgillivray, Naturalist 
to the surveying Expedition of H. M. S. Battle- 
snake, thus describes his net; "not having seen a 
description of this useful instrument I may men- 
tion that the kind used by Mr. Hutley and my- 
self consisted of a bag of * bunting' (used for flags) 
2 feet deep, the mouth of which is sown round a 
woodenhoop 14 inches in diameter. Three pieces of 
cord a foot and a half long are secured to the hoop 
at equal intervals,andhave their ends tied together. 
When in use the net is towed astern, clear of the 
ship's wake by a stout cord secured to one of the 
quarter boats or held in the hand. The scope of 
line required is regulated by the speed of the 
vessel at the time and the amount of strain caused 
Fig. I. 
Fig. n. 
by the partially submerged net." In Darwin's voyage of H. M. S. 
