The Collection of Historical Scientific Instruments (CHSI) is always free and is located inside the Science Center on Harvard's Cambridge campus, at 1 Oxford Street, near the corner of Oxford and Kirkland Streets. The Putnam Gallery is open 11am-4pm Sunday through Friday,

The CHSI is one of the four Harvard Museums of Science & Culture (HMSC).

The Collection of Historical Scientific Instruments at Harvard advances the educational and research needs of the Harvard community and beyond, engaging visitors through guided access to collections, experimental exhibitions, and innovative programming.