. >> host: a brief interview with james salzman who has written a history of drinking water. this is booktv on c-span2. >>> now, clay risen accounts the civil rights act of 1964. recalling the arduous work involved in passing the legs, marked we bun of the longest filibusters in history by opponents who south to defeat the measure. this is an hour and ten minutes. >> host: clay. a terrific book. >> guest: thank you. >> host: a terrific book on an important topic, and you don't