364 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
dragging over rocks or other uneven surfaces. It is held in position by the eyebolt </, 
which is square and fits snugly in square holes in the arm and bov7. 
The tangles are, in material, size, and structure, practically the same as the deck 
swabs in general use on board ship. 
THE TABLE SIEVE. 
The table sieve, plate xxxiv, fig. 2, is an outgrowth of the cradle sieve, fig. 1, 
which was formerlj^ used for washing the contents of the dredge, the more bulky loads 
of the trawl having been emptied on deck. The first table sieve was devised by Capt. 
H. 0. Chester and Prof. A. E. Verrill, and consisted of a rectangular table supporting 
a fine sieve, and over it the hopper with its coarse wire netting. The canvas bottom and 
chute were added by Mate James A. Smith,. U. S. N., executive officer of tbe U. S. S. 
SpeedireU, while in the employ of the United States Fish Commission, about 1877. 
To iirepare the table sieve for use, place the sieve c in the frame a on cleats 
jirovided for it a few inches above the canvas bottom d; then place the hopper in the 
frame over the sieve and carry the chute c to a scu])i>er. 
The table legs are now made detachable, Avhich materially reduces the sjjace 
required for stowage. 
THE CRADLE SIEVE. 
This sieve was devised by Prof. A. E. Verrill, in the early days of the United 
States Fish Commission, for the purpose of rapidly washing out the mud bi'ought up 
by the dredge. It has wooden ends, nearly semicircular in form, joined bj^ narrow 
strips which are let into the end iiieces so as to present a smooth surface. A fine 
netting is drawn over the surface, and supported by an outer netting of coarse mesh 
secured firmly to the ends and side pieces. An inner sieve with coarse mesh rests on 
and partially inside of the main sieve. It is intended to be hung over the vessel’s 
side by means of a rope bridle attached to iron straps on the end pieces. 
THE STRAINER. 
The strainer, fig. 3, was introduced on board the Albatross, in 1883, by Mr. James 
E. Benedict, resident naturalist, for the purpose of straining all water used for washing 
mud and ooze from specimens in the table sieve. By this means minute forms of 
Crustacea, annelids, foraminifera, etc., are recovered at small expense of time and labor. 
Its construction is very simple. An oil barrel was cut down until it would slide 
under the table sieve. Three iron drain-pipes are inserted in the side, one diagonally 
over the other, and attached to them are three strainers, a, h, and c, made of linen 
scrim, through which the water is drained as it rises successively to the level of 
each. Tlie combined areas of the three are sufilcient to carry off the Avater supplied 
by tlie steam hose under ordinary circumstances. When it is to be used in connection 
with the table sieve the long chute e is removed, and a short one abont a foot in length 
is substituted, the water being discharged directly into the strainer. 
THE TANNER IMPROVED DREDGING QUADRANT. 
The dredging quadrant (plate XXXA^) in its original form was designed by the 
writer as the most convenient and practical method of ascertaining the position of 
traivl or dredge in deep-sea e.xploration by observing the angle of the dredge rope. 
The present form is simply a refinement of the original. 
