Niobium capacitor
The development of solid electrolyte tantalum capacitors began in the early 1950s as a miniaturized, more reliable low-voltage support capacitor to complement the newly invented transistor. The solution found by R. L. Taylor and H. E. Haring of the Bell Labs was based on experience with ceramics. They ground down tantalum to a powder, pressed this powder into a cylindrical form and then sintered the powder particles into a pellet (“slug”) at high temperatures, between 1500 and 2000 °C, under vacuum conditions. These first sintered tantalum capacitors used a non-solid electrolyte not consistent with the concept of solid state electronics. 1952 a targeted search in the Bell Labs for a solid electrolyte by D. A. McLean and F. S. Power led to the invention of manganese dioxide as a solid electrolyte for a sintered tantalum capacitor.
Condenser (laboratory)
The condenser known as the Liebig type, a most basic circulating fluid-cooled design, was invented by several investigators working independently; however, the earliest laboratory condenser was invented in 1771 by the Swedish-German chemist Christian Weigel (1748–1831). Weigel’s condenser consisted of two coaxial tin tubes, which were joined at their lower ends and open at their upper ends. Cold water entered, via an inlet, the lower end of this jacket and spilled out of the jacket’s open upper end. A glass tube carrying vapors from a distillation flask passed through the inner tin tube, not in contact with the cooling water. Weigel subsequently replaced the inner tin tube with a glass tube, and he devised a clamp to hold the condenser. In 1791, the German chemist Johann Friedrich August Göttling (1753–1809), who was a former student of Weigel, sealed both ends of Weigel's condenser. The German chemist Justus Liebig (1803–1873) eliminated the inner wall of Weigel’s condenser, placing, in direct contact with the jacket’s cooling water, the glass tube carrying vapors from the distillation flask. He also replaced, with glass, the outer metal wall of Weigel’s condenser. And he used rubber hoses, instead of metal tubes, to convey water to and from the condenser.