there's also several false alarm rides he did before april 18 which is why warren sent dawes as a precaution and waited until he saw firsthand that the british were mustering the boston common before sending revere because he didn't want to send another false alarm and it was because of the previous false alarm that revere set up the plan that if he got trapped in the town of boston, that the lanterns, one if by land, two if by sea, because he was concerned that after that there might be british soldiers roaming and he wouldn't be able to get around them. any other questions? all right. [applause] derek: thank you for coming out. >> thank you for coming tonight. books will be on sale in the back and derek will be signing copies. i hope to see you next month for the evening lecture. [captions performed by national captioning institute] [captions copyright national cable satellite corp. 2016] this evening at 6:00 eastern at , a professor talks about how photography can be used to chart the history of american slavery the for and after the emancipation. >> we spent a fair amount of time with fr

several false alarm rides he did before april 18 why warren sent dawes as a precaution and waited until he saw firsthand that the british were mustering the before sending revere because he didn't want to send another false alarm and it was because of the previous false alarm that revere set up the plan that if he got trapped town of boston, that the byterns, one by land, two if sea, because he was concerned that after that there might be roaming and hes wouldn't be able to get around them. questions? all right. [applause] derek: thank you for coming out. [captions performed by national captioning institute] [captions copyright national cable satellite corp. 2016] >> thank you for coming tonight. sale in thee on back and derek will be signing copies. next month forou the evening lecture. >> you are watching american history tv on c-span3. to join the conversation, like us on facebook. now the contenders, our series on political figures who ran for president and lost and changed political history. tonight we feature al smith, the in 1928.c candidate this program was recorded at the new y

there are several false alarm rides that he did before which as ay warren sent dawes precaution and waited until he saw firsthand that the british were mustering at boston commons becauseending revere you do not want to send another false alarm. it was because the previous false alarms that revere set up a plan that if you got trapped in the town of boston with a lantern, he was concerned that after that that there might be british soldiers roaming it would not be would get around them. questions? thank you for coming up. -- out. [applause]