Marine bottom sampler
John M. Brooke had been an young naval officer belonged to the U. S. Naval Observatory and Hydrographical Office in 1854. The head of that office was the Commander Fontaine Maury who was well known as charting ocean currents. Brooke submitted a marine bottom sampler like a figure. E was the shot, 64 lbs, and there was a hole pass through the center, and an iron stick penetrated. At the bottom of a stick, there was an hole putted in with an animal fat. Put a woody cap in a fat and put it out to make a space. The shot had been held up with a line as B, C, D, and when the stick hit a bottom of the sea, the line would had moved like on a figure and if you lift up the wire, the shot would be left on a bottom of the sea. It meant some substances of the bottom of the sea had to have been picked up and a water reistance at lifting a weight would be reduced.