70 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [6] 
Along these chains, at intervals of about three feet, the bundles of un- 
raveled hemp rope were attached, as shown in the figure. The bar of 
iron carrying the chains was attached to the cross-bar of the A-shaped 
frame forming part of the rake-dredge, the rake-bars being removed. 
In 1873 a farther improvement was made by the writer. This consisted 
in supporting each end of the chain-bar in the center of a stont iron hoop 
or wheel, by bolting it to a central cross-bar, firmly bolted to the inner 
side of the wheel. The wheels are not intended to revolve, but merely 
to serve as runners and supports for the iron bar, in order to keep it off 
the bottom and diminish the chances of its getting caught among the 
rocks, as well as to keep it from breaking and destroying the specimens 
before the tangles themselves can touch them. An oval or elliptical 
form for these runners would answer the same purpose, but the circular 
form was adopted as the simplest, and perhaps the least liable to become 
caught among the rocks. 
In practice we have found the tangle-frame hitherto used too light for 
use on the larger vessel now employed, for when rocks are encountered 
the chain-bar often comes up badly bent. In constructing new ones, I 
should recommend a round or square bar of iron at least twice as heavy 
as the one we have hitherto used. Our present size was first devised 
for use on a steam-launch. It was also used on the Blue Light, a tug of 
80 tons, with good success. The chains proved to be unnecessarily long, 
and are now shortened. We have used tangles of this form with profit 
on the roughest cod-fishing ledges off the coast of Maine and Massachu- 
setts, where the dredge could not be used with safety. 
It is particularly useful in capturing star-fishes and sea-urchins, which 
frequent rocky bottoms. Several years ago the writer suggested the use 
of tangles of this or some similar form to capture star-fishes on oyster- 
beds, where they so often prove very destructive. 
Dimensions of tangles. 
Dae Improved 
Present form. design. 
Diameter of wheels outside ........-...--..--- Bodbqaacobsshsnbdusanadadesce 12inches ...| 14 inches. 
Breadth! of rim of wheels) - h\..css< cin sas onlo see c eee oe epicle siasocee ae cles meaiacie 2inches....| 24 inches. 
‘Ehickness'of rim‘of Wheels. co sckasecs ct eeeis sce om cco ceoeiniseucecleeeeentece 4 inch.....- | inch. 
Width of: cross-bariof. wheels <i cctecws cede ease ce pees Heidseseiocelns aaseenneaee 2inches....| 24 inches. 
suhieknesstofcross-bar Of wheels)-cesceeteeccere seb eane tas ee tee eeE eee nee finch ese. inch. 
Mencth Of Chain-bar . ss: :1jacjsc ceed Serco a se hee ee oe see eee oe ee eee ... | 60 inches. 
Wdiihvot chain-bar << 5_).0. 5245 5a vanes sb ee eee ona re cee eee See eee ieee | 24 inches. 
Thickness of chain-bar .....- ? 1 inch. 
Size of rings for drag-rope- -.| 4 inches. 
Size of iron of rings ....- § inch. 
Size of iron of chains...- % inch. 
Length of iron chains. ..- ) 10 feet. 
ihren sthiofehempitangles' =... cscs wecece) sence secene teseee 2.5 fe 3 feet. 
The drag rope for the tangles should be very strong, to resist the fre- 
quent and sudden strains, when using them on rough bottoms. 
