A quick Google search turned up nothing new on John Hay. There was a small book published in 1978 about Hay by Robert Gale, but I'm not familiar with it.
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Rob
Abraham Lincoln is the only man, dead or alive, with whom I could have spent five years without one hour of boredom.
--Ida M. Tarbell
I want the respect of intelligent men, but I will choose for myself the intelligent.