This Braille code was never accepted for use by the British Braille authorities. The code achieved inroads into 19 schools for the blind in the United States, including the Boston school, where it was invented by a blind teacher named J.W. Smith in 1878. The feature of the alphabet was that the most frequently recurring letters are represented by the smallest number of dots. It could therefore be written and read quicker. It's competitor in the United States was New York Point.
Advocates of American Modified Braille code realized the need for a universal English language Braille code that would unite American and British literature into one code. This would not happen until the early part of the twentieth century.
Joel Smith, a piano-tuning teacher at Perkins School for the Blind in Massachusetts, developed the American Modified Braille Code in the 1870’s. When developing his system, Smith designed characters he believed would be fast to read and an efficient use of paper. The alphabet is based on the premise of the most frequently used letters would have the fewest dots.
The code was adapted in 1892 by several schools for the blind. Others schools, including this one promoted New York Point. A further complication was that Great Britain was using a form of what we would today call Grade 2 braille. This meant that avid readers and scholars would need know all 3 codes to make use of the available literature.