An excellent set of short studies to master shifting, published in 1928. They encompass shifts that start at multiple positions and train skips as high as one octave intervals. Yost's etudes are a common source for technical improvement for students of any age. Mr. Yost provides the following instructions to his position studies. - Each measure must be repeated at least ten times before passing on to the next. Practice slowly. - Use great care in keeping the thumb free. Do not press it too firmly against the neck of the instrument. A disregard of this important rule [can cause problems in the pupil's shifting technique]. - In changing positions, the slide is executed with the finger used before the change and the finger must not press the string too firmly during the slide (shift).