COMING UP: According to renowned US author and critic Jed Perl, Alexander Calder remains America’s greatest sculptor. Based on unprecedented access to Calder’s letters and papers, Perl is completing the first biography of this artist. It will be published by Alfred A Knopf later this month. Easel Contributing Editor Morgan Meis recently talked to Perl about the project and its famous subject. The interview will appear in The Easel at the end of October.