A Houdini and Nate Mystery

I am have came to a point in my reading where Nate and Houdini are now trying to find the assasinator which tried to kill the former president Roosvelt. Nate remembers that the asasinator had a very big coat a very tall black hat and a grey beard because probably he was old. nate had estimated that the man is old around sixty yeras old. Although there is 4000 people on the shop Nate and the great magician Houdini will try there best to solve this mystery.