Which laboratory glassware is named after a German chemist?

The Erlenmeyer flask, designed by Emil Erlenmeyer in 1860 - a conical body with a flat base and a narrow neck, which is one of those objects so well shaped for its job that it has not needed changing in over 160 years.

Every feature does something. The flat base stands on a bench; the sloping sides mean you can swirl the contents to mix without a stirrer and without slopping; the narrow neck reduces evaporation, takes a stopper, and lets you hold it in one hand while titrating with the other. A beaker does none of that and a round-bottomed flask will not stand up.

Erlenmeyer himself is better remembered for chemistry than for glass. He formulated the rule that carbon atoms carrying two hydroxyl groups are unstable and collapse to a carbonyl, which explains why a great many plausible-looking molecules simply cannot exist, and he was among the first to argue that the four carbon bonds in ethylene had to be arranged as a double bond - part of working out that molecules have shape at all.