1848 



Description of BalVs Dredge. 



it has met with the universal approbation of all British naturalists, and I hope that 

 the accompanying figure and description of this dredge may prove acceptable to the 

 readers of the ' Zoologist,' and sufficiently explicit to enable any one to direct a coun- 

 try blacksmith in its construction. In the practical use of the dredge, I have no ex- 

 perience, but hope, ere long, " to be afloat.'' 



Ball's Dredge. 



The figure represents the dredge mounted and prepared for action : the two scra- 

 pers ABCD and ABCD are each twenty inches in length, by two inches in breadth ; 

 parallel with their lower edges CD and CD, about fourteen holes, equidistant from each 

 other, are pierced to receive the laces of the bag, and these two plates are joined at 

 their lower extremities, by means of two cross bars CC and DD, so as to form an 

 angle of about 45° with the plane of this position ; each crossbar is five inches in 

 length, by three and a half eighths in diameter : the arms EF and EF are each six- 

 teen inches in length, by three-eighths in diameter, and play upon the cross bars by 

 means of double swivel joints, as seen at EE and EE. Their anterior extremities at F 

 are beaten flat, so as to meet closely and vertically, and are pierced for the reception of 

 the bolt H, which, at the same time, passes through the extremities of what may 

 perhaps be termed the bridle ring G, to which the rope is affixed. The head of the 

 bolt H is pierced to receive the end of a little iron spike for the better working of the 

 screw, and at any time, by drawing the said bolt H, and folding the arms inwards, the 

 whole apparatus may be stowed away in a moderate sized carpet bag, for its weight 

 will not exceed seven or eight pounds, and the cost of one made by Messrs. Sibbald 

 and Sons, George-street, Edinburgh, is only seven shillings ; the above description is 

 taken from one of their manufacture, and it is the favourite size of such as they have 

 made for Professor Edward Forbes and J. Goodsir. In no case should the bag ex- 



