Take the Montenvers train from Chamonix town to see the Mer de Glace or "Sea of Ice" and visit this small museum.
After a scenic train ride and stunning views over the glacier a visit to this small museum is recommended.
See the documents on the Mer de Glace and the construction of the Montenvers railway, along with ancient objects, old prints, and a beautiful collection of crystals makes for a interesting day out.