You need launchers(2) in addition to mechanics(6) to make a chemical thrower. Weird, I know. I wrote a post about my experience with chemical throwers last month.
On the plus side, I’ve found as many as seven or eight lumps of sulfur near a lava rift before, which makes the sulfur requirement a little easier. But it’s still pretty hard to justify not just burning the fungal bastards.
Also, you should categorize your post, it makes it more visible.