According to Readers Guide to The Mahatma Letters to A. P. Sinnett:
Babula, HPB's personal servant whom she hired in Bombay soon after her arrival there. He was 15 years of age at that time and is credited with being able to speak six languages. See ML index; ODL 2: 21; LBS, pp 166-7. 
- George E. Linton and Virginia Hanson, eds., Readers Guide to The Mahatma Letters to A. P. Sinnett (Adyar, Chennai, India: Theosophical Publishing House, 1972), 218.