This information was found in the Bristol town records, p. 43 of the old marriage listings. I have a photocopy.
It is also listed in James N. Arnold's Index of Vital Records for Bristol (a tan library-bound book).
Lucinda had a twin sister who died six days after birth.
William A. & Lucinda Manchester are living at Bristol, RI, in the 1860 Federal Census. He is 26 and she is 18. They are in the household of Martha Manchester, probably William's mother.
In 1870 William & Lucinda are still at Bristol. In the household is their young son Walter, age 3. Also there is Lucinda's first cousin, Emma J. Chafee, 16. (Their fathers are brothers.)