"The dam down there would necessarily be about thirty feet high at the center, and people driving along the roadway would not be able to see the water at all.

They would only see the blank wall of the dam.

Of course we could soften that by building the dam back a few feet from the roadway, making an embankment and covering that with turf, or possibly shrubbery or flowers, but still the water would not be visible, nor the hotel!" "I see," she said slowly.
They both studied that objection in silence for quite a little while.
Then she suddenly and excitedly ejaculated: "_Sam_!" He jumped, and he thrilled all through.

She had called him Sam entirely unconsciously, which showed that she had been thinking of him by that familiar name.

With the exclamation had come sparkling eyes and heightened color, not due to having used the word, but due to a bright thought, and he almost lost his sense of logic in considering the delightful combination.