“Yesterday I received a letter from my father [ Dutch landscape-painter J. W. Bilders.] He told me to come at once, to paint the goats in a rather large forest landscape-painting he just finished, which has to be sent away at once [to Saint Petersburg, Russia]. I earn back my travelling [from Leiden to Amsterdam, probably by travel coach] but will loose one day studying in open air. When my goats will succeed, and they are not too stubborn, I'll be back here [in Leiden] tomorrow at one o'clock in the afternoon.”