RAY: Hi, we're back. You're listening to Car Talk with us, Click and Clack, the Tappet Brothers, and we're here to discuss cars, car repair, and the new puzzler.

TOM: We are on top of things, you know.

RAY: I've lately taken to reading some of my old mail.

TOM: I can see that.

RAY: And this puzzler suggestion came from a guy named Benjamin Shultz, who at the time looked like he was probably a high school student, or maybe an elementary school student.

TOM: Probably got four kids now, driving a mini van.

RAY: The letter was sent 12/31/94. Well, here it is.

TOM: Well, that's only five years. Yeah, he could be married with four kids.

RAY: He could. He could indeed, if he's a fast worker. Now, first of all, I should mention that this is the first in the series of World War I puzzlers.

TOM: World War I! You have all these little series.

RAY: Yes.

TOM: Gus?

RAY: Yeah.

TOM: And Crusty?

RAY: Yeah.

TOM: String?

RAY: String, pendula.

TOM: Pendula?

RAY: Matchsticks.

TOM: Oh, yeah the matchsticks. The famous matchsticks series.

RAY: Oh yeah.

TOM: Oh, that was great!

RAY: This is just the first in the series of World War I puzzlers.

TOM: World War I, OK.

RAY: And here it is. In the beginning of the first World War, the uniform of the British soldiers included a brown cloth cap. They were not provided with metal helmets. What were they thinking?

TOM: What were they thinking?

RAY: As the war went on, the Army authorities in the war office became alarmed at the high proportion of men suffering head injuries.

TOM: Yeah.

RAY: They, therefore, decided to replace the cloth head gear with metal helmets. From then on, all solders wore the metal helmets.

TOM: Good idea.

RAY: However, you ready for this?

TOM: Yeah.

RAY: The war office was amazed to discover that there were more soldiers hospitalized with head injuries than ever before. It can be assumed that the intensity of fighting was the same before and after the change.

TOM: Yeah.

RAY: So, why should the recorded number of head injuries, why should the number of soldiers hospitalized for head injuries per battalion, increase when the men were wearing metal helmets rather...

TOM: Instead of cloth?

RAY: ...than cloth caps? Now, if you think you know the answer, send that answer to the Puzzler Tower...

[ Car Talk Puzzler ]