![](https://coimages.sciencemuseumgroup.org.uk/715/medium_thumbnail_1993_0675__0002_.jpg)
Two examples of the Hemispherical or "Kettledrum" condensor
![Two examples of the Hemispherical or Kettledrum' sub-stage](https://coimages.sciencemuseumgroup.org.uk/313/568/medium_smg00029288.jpg)
Two examples of the Hemispherical or "Kettledrum" sub-stage condenser, introduced by the Rev. J.B. Reade, one engraved "98", one "463"
Two examples of the Hemispherical or "Kettledrum" sub-stage condenser, introduced by the Rev. J.B. Reade, one engraved "98", one "463"