I’ve been reading SCIENTIFIC AMERICAN regularly since around 1995–about 15 years.  This is long enough to remember when the "50, 100 & 150 years ago" department referred to, say 1945, 1895 and 1845 respectively.  It is therefore a little unsettling to see the column appear today with "March 1960" (50 years ago), "March 1910" (100 years ago) and "March 1860" (150 years ago).  It is,in fact, another sign how just how quickly time flies…