This is a wonderful collection of stories. To be honest, not all are about "mad" scientists, though most do have scientists (some mad, some not) as protagonists. But it's a fun read with some classic and some little known stories. Some of the best names in the science fiction and horror field are represented: H.P. Lovecraft. Edgar Allan Poe, Robert Bloch, Ray Bradbury, M.R. James, Ramsey Campbell, Dennis Etchison, Arthur C. Clarke and others.
I've always loved the "literary pulp" era from the mid-1950s to the mid-1970s, when authors like Robert Bloch, Ray Bradbury and Stephen King wrote increasingly challenging and ambitious, literary but "genre" based, short stories for the men's magazines and anthologies of their era. As a teenager and then an adult, I read as many anthologies of that kind as I could find, and few are as good as this little-known compilation I discovered probably when I was six. I had little to no way of relating to some of the heavier stories in here, but I remember my dad telling me the story of "Sardonicus" on my great-grandfather's porch.
The stories here are mostly top-notch; "Sardonicus" by Ray Russell is the most famous, but lesser-known tales like "At the Bottom of the Garden" and "Sylvester's Revenge" pack a punch too. My favorite, however, is the story that has aged the worst: "The Fourth Seal" by Karl Edward Wagner. What if all the conspiracy theories were true? What would you do then? It's an all-too-timely tale to read during the pandemic and political unrest of 2021 America, and I'm almost glad it was never made into a movie... too many people would believe it.
Summary: A niche collection of stories, but you'll find something to like if science fantasy is your thing.
I can't speak for a veteran fan of the genre, but as a novice to horror, I found some of these tales to be chilling. The best aspect about this anthology is the variety, which Schiff details in the foreword was his intention. Not all of them were chosen for being scary, or even unsettling (I think specifically of Robert Bloch's "The Strange Island of Dr. Nork" and Ray Bradbury's "A Scent of Sarsaparilla" as examples of this). But they were chosen for their depictions of "mad" scientists, or science as a whole. And that's why I mostly enjoyed this anthology. It was a random find at the library in an attempt to check out something scary to read for October.
The pieces in this collection are mainly from the early- to mid-1900s, which is perhaps my favorite era of science fiction prose. No two 'mad scientists' are alike in these stories - some you laugh at, some you recoil from. To my jaded, 21st-century mind the science-based plots weren't particularly scary but, given a shadowed room on a dark and stormy night, there would be some chilling tales in the bunch.