From the book:
At Overbrook, [School for the Blind] Dr. Davidow was instrumental in establishing the use of the Cranmer Abacus as a part of the regular curriculum. Her enthusiasm for this pioneer method of teaching mathematics led others to adopt the use of the abacus. In her role as coordinating teacher, she worked with the members of the Mathematics Department and the results were highly successful. Hopeful that this success at Overbrook might be experienced by many teachers elsewhere, she was encouraged to write this manual.
Her goal was to write a clear, simple manual which could be used by teachers or students. This book represents her achievement.
