Declaration of the National Anti-Slavery Convention was written by William Lloyd Garrison for the formation of the American Anti-Slavery Society in December 1833. It was reprinted in The Liberator on December 14, 1833. It is now available in the Public Domain.
You can also use the Optimized PDF option to crank the size down in very targeted ways. Given the big before/after shift, the culprit is probably the image you're embedding. Try exporting that file in various formats (PDF, jpg, png) and then import it.
How to reduce file size when print to pdf. When separating pages out of a file and using microsoft print to pdf or foxit phantom pdf printer to create a new a document, the new document is huge. Over twice as large as the original document. Never had this problem with Windows 8, just since I updated to windows 10.