This is a part of the "chronohyometer" invented by Marsilio Landriani c. 1780. The instrument was originally a pluviograph (rain gauge). It consisted of an open-air collector that conveyed the rainwater into a small funnel connected to a moving lever. The filling of the funnel caused the lowering of the lever. This, in turn, actuated a white pencil that left a mark on a blackened disk, driven by clockwork., The funnel was periodically emptied through a small glass siphon into the rain-gauge container. This consisted of a cylinder closed at the bottom and fitted with a faucet and vertical tube. The quantity of rain was measured in the container. A series of small glass siphons, used to empty the funnel, has survived.