The pub Claire and Jamie go to in Edinburgh, The Worlds End, is still there and operating as a pub.
The first episode in the series where there is an introductory segment before the title sequence. Also the first episode where part of the credits are integrated into the chapter title shot, showing them as papers printed by Jamie.
Jamie questions what Claire hands him, and she says they are called photographs. Modern photography dates back to the 1820s but the basic idea has existed since ancient times. Even as early as 1717 there were attempts at capturing an image. But none of these earliest attempts were well known amongst the general public. The first commercial photography methods weren't introduced until 1839.
Jamie refers to soda ash. This is a dry chemical that is mixed with printer's ink to ensure consistency and proper absorption into the paper.