This week's photo is a classic photo of the ladder dredge Corozal from a personal photo album.  The date is not known, but it was taken before the Canal was open.
      It is puzzling that the Corozal is shown here in the Culebra Cut near Gold Hill because it was designed to dig only soft material and this area of the Cut was all rock.  It must have been brought in to assist with the digging of a slide consisting of dirt and not solid rock.

      From The Panama Canal Review April 6, 1962 issue:

The ladder dredge Corozal went to work in the Pacific entrance of the Canal on April 15, 1912.  The drege had arrive at Balboa on March 27 after sailing 12,064 miles from Clyde, Scotland, where she was built for the Canal organization.  The trip required 117 days,96 of which were actual sailing time. Capable of excavating 1,200 tons of soft material an hour from a depth of 50 feet, the Corozal was scheduled for use in digging an estimated 4 million cubic yard of material from the Pacific entrance to the waterway. 

     From Dredging the Panama Canal by John G. Claybourn:

The modern twin screw ladder dredge, Corozal, had mud buckets of 54 cubic feet capacity and rock buckets of 34 cubit feet. The last named dredge, the Corozal, was purchased with the idea of avoiding delay and expense in breaking or blasting in cutting  through the softer rocks to be encountered between Balboa Wharf and Miraflores Locks.  This plant proved to be successful in performing this class of, the output varying from 3,000 to 10,000 cubic yards of rock per 24-hour day.  The harder parts of rock were handled by cutting six-inch layers, the softer  as much as four feet at one passing of the dredge.  This dredge was also very efficient in handling mined material.  However, it could not dig its own floatation and also was not suitable for slide work where large pieces of rock were encountered.

Some of you may remember the scale model of the Corozal on display in the Civil Affairs Building. I wonder what happened to it?