If you are searching for arrivals in Boston using ancestry, NARA films or FHL films, you will not find any arrivals between April 1, 1874 and December 31, 1882.

Apparently these records were lost in a Boston fire in May 1894. When searching ancestry, no mention is made in the database description that there are almost 8 years of missing manifests.
=================================
The Commonwealth of Massachusetts has records in the Massachusetts archives that replicate many of these missing records. From their on-going volunteer project, at least 76,498 records exist for the missing timeframe.

You can search them at:
http://www.sec.state.ma.us/arc/arcsrch/PassengerManifestSear...