But Heller has gone much further than this in her search for authenticity. Everything in the letters is carefully considered. The texts include occasional flaws so that they resemble letters written by real people, and they are even accurately folded for the time period. Since letters at the time weren’t usually sent in envelopes, they were specially folded in a way that protected the contents and were traditionally sealed with wax. If you look closely, you can see lots of little period details – you have the stamps from the sender’s postmaster and the arrival stamp, and the price which was based on how far the letter had to travel and was originally paid by the recipient not the sender. In several cases where only a fragment of the letter appears in the text, the letters have been thoughtfully extended based on the novel and the time period into a full letter you can read and enjoy.