This is the expanded version of his 1966 short story “Light Of Other Days.” There were two more stories, “Burden Of Proof” in 1967 and “A Dome Of Many-Colored Glass” in 1972. All three are incorporated in the novel as sidelights. It’s all about an interesting invention called Slow Glass. Light travels through it so slowly that you can see five minutes or five years ago on the other side.
Alban Garrod makes windshields. He strikes it rich after discovering Slow Glass. It has a multitude of uses from scenic windows to spy devices. It’s been a great aid in solving crime. The next step is to try and make the images speed up so you wouldn’t have to wait years for the images to play out. That leads to a tragedy involving Garrod’s wife, Esther.
After a while the public is turning against the invention. Privacy leagues are popping up. They destroy the Glass that lines roadways. Garrod is called to Maine to solve a murder. He finds out he’s just being used. What are those crop dusters all about?
The novel is okay but I liked the short stories (sidelights) better. Still, it’s worth picking up but not a priority. Hunting up the short stories is the best bet.