These four tugs were photographed in the mid 1970's at the scrapyard of Davis and Cann on the River Plym, Plymouth. They were the entire fleet of WJ Reynolds and were perhaps the last fleet of tugs in one company that all had coal fired boilers. The camera used was my much loved Mamiya Press with a 90mm f/3.5 Mamiya Sekor lens.
One of the keys on the ancient typewriter I inherited from my aunt - normally a 'Shift' key for upper-case letters, numbers or signs - was, on this typewriter, called a 'Floating Shift' - presumably for its light-as-a-feather or floating-like-a-gentle cloud usability---
I believe the 'Floating Shift' was used for individual caps/upper case, such as the capital at the beginning of a sentenceor a proper noun(John Smith). Just above it is the 'Shift Lock' for a string of upper case such as the title of a piece. (HAMLET)