Useful links when researching vintage patents

European Patent Office —

My goto resource for vintage patents. Great search facilities and worldwide coverage.

Google Patents —

Google's search engine for patents. Quite good, but I prefer the EPO's user interface. Quite often Google links to the EPO website for details.

U.S. Patent Office —

This site also has trademark information, but the user interface is often confusing and it only covers U.S. documents.

The Lens Patent Search —

A good resource when searching by inventor names.

PatBase —

A commercial patent database, but they have a free “patent classification explorer”.

Patent History Materials Index -

From the University of New Hampshire. Lots of original patent resources from the 19th century.
They also have the complete text of A History of the Early Patent Offices: The Patent Office Pony by Kenneth W. Dobyns

Useful links when researching historical information

FamilySearch —

A very good website run by the Mormon Church. First port of call for births, marriages, immigration, census information and deaths.
Some of the information is not accessible from the internet, but only from affiliated libraries. My local UK library is one of them. You can find documents using the computers at the library and email them to yourself.

Find A Grave —

Good for deaths, but only good for deaths.

FreeCen —

UK census information up to 1891.

New York Times archive

I can no longer recommend the New York Times archive as a source.
It's a paid subscription that is almost impossible to cancel.
The venerable New York Times has turned into a scam. —

Paid subscription, but can be cancelled anytime without problems.