Robert Bruce, through mostly vignettes of the interactions between President Lincoln, the military officers responsible for testing and purchasing new weapons, and the inventors and backers of the many schemes for new weapons weaves a fascinating story. The President, with an open mind and a Let's Try attitude, the inventors mostly earnest and patriotic though often "odd", the backers many painted as unscrupulous, and the military who ran the gamut from progressives to stalwart conservative who would have used the weapons of their fathers if given the chance.
Bruce shows that the time was one of immense technological advancement. Among the many "modern" weapons getting a first look were the machine gun, the breechloading rifle, the rifled cannon, the submarine, and the torpedo. Lincoln had two notable successes in his dealings with the Ordnance chiefs - the introduction of the machine gun and the acceptance of breechloading rifles. He pushed many weapons which ended dubiously and the machine gun that was ordered, the Coffee Mill Gun, did poorly in the field but it lead to the much-improved Gatling gun which faced none of the largest hurdles to service acceptance.
The author introduces enough background on each of the characters to give the reader a good grounding of the events then related in the vignette. He also makes sure to complete each story so that the reader is left satisfied that each small story is complete.
While not a book about the great decisions of Lincoln, the battles, or the campaigns and generals, this is a fascinating look at the technological and bureaucratic end of warmaking, at a time of rapid technological advance. It paints a side of Lincoln, the mechanic, the tinkerer, not often seen.
Me as a critic (be careful! the harshness will be well concealed!)