Spirometer used by music teacher Arnold Jacobs to test his students. From “Arnold Jacobs – Breathe like a baby, play like an angel”. ITG Journal, May, 1999, page 18.
Spirometer used by music teacher Arnold Jacobs to test his students. From “Arnold Jacobs – Breathe like a baby, play like an angel”. ITG Journal, May, 1999, page 18.