A new $100.000 astronomical observatory to house Harvard's invaluable collection of photographic plates of the heavens is to be built on Observatory Bill in Cambridge it has been announced by Dr. Harlow Shapley of the Harvard Astronomical Observatory.

The building, which will probably be started this spring, will be three stories in height and will include a two-story vault that will have a constant humidity and temperature in order to secure the safety of the photographic plates which are valued at more than $1,000,000.

In the past this rare collection of plates has been inadequately housed in an old building which is not fireproof and which left the plates exposed to heat, humidity, and the ravages of time.

Harvard's collection of stellar photographs, which now comprises more than 350,000 plates, was begun in 1850 by Professor Bond, at that time director of the Observatory. It is now five times larger than any other single collection of its kind in the world.

The plans for the new building also include a third floor entirely given over to offices, a lecture hall, several meeting rooms, and a library, also fire-proof, to house the valuable collection of 65,000 volumes and pamphlets, which ranks second only to that of the United States Naval Observatories at Washington. It is expected that the new building will take care of additions to the books and plates collections for the next 40 years.