In order to understand Icebergs drift, the International Ice Patrol (IPP) used different tracking systems. One early method used glass tipped arrows dipped in dye.
The use of dye for tracking was later stopped as the dye dissapeared with melting and the iceberg rotation.
From the International Ice Patrol
The IPP monitors the iceberg danger near the Grand Banks of Newfoundland and provide the iceberg limit to the maritime community.
On Fogo Island, Newfoundland, ice is collected off the shore in spring from broken bits of passing icebergs on their way south through “Iceberg Alley.” The ice is used throughout the year as ice cubes and in ice boxes.
From 4 Dimensional Mapping project. Photos courtesy of Yvonne Mullock and Erika Irmler