Apologizes for not having written, but has been 'harassed with desultory and importunate calls on [his] name.' Commends WS on accomplishments at Pulkowa and performance of Repsold instruments. Congratulates WS on his son Otto Struve. Received WS's figures on Halley's Comet. Comments on bright stars of variable nature. Estimates 35 or 36 magnetic observatories in the world.