REMOVE

1. Slate
2. 5 slate chalkboards
3. Roxbury

WHAT

1. blackboard slate (5)
2. image-making equipment (5)

WHERE

1. Roxbury, Massachusetts (5)
2. UMass Archaeological Serv … (5)

WHEN

1. 18th-20th century (5)
2. 19th-20th century (5)
3. creation date (5)