English Vertical Vibrograph, 1930's. 20th Century. Working As The First Day

Curious English Vertical Vibrograph made in the 1930s by Cambridge Instrument Co. Ltd. Vibrographs are devices which detect mechanical vibrations and charts them. They work with a moving stylus which records the vibration being measured on a roll of moving paper. This kind of instruments started being used to record vibrations caused by controlled explosions (in the construction field), and afterwards they were also used when driving and operating heavy machinery. This particular instrument was made by one of the most prestigious companies of scientific material, which was ruled by the youngest surviving son of famous naturalist Charles Darwins. The company started as workshop created by Cambridge University in 1898 to make the instruments they needed for their investigation. In 1968 it was purchased by George Kent who split it into four divisions, each of one was eventually sold off. This vertical vibrograph is in good condition. It is also in good working order and comes with its original wooden case, with the operating instruction attached to the covers inside. The device is electrically powered, by means of a connect-maker and a 4 volt accumulator which sould be connected to the two terminals at the back. Nevertheless, the instrument can also be operated mechanically by winding the key also at the back. The mechanism turns the top cylinders which carry the paper roll where the stylus records the vibrations. At the rear we can see the vibrographs serial number (C163919) and the patent number (195116). The instrument can be operated today as if it were new. The case which houses the article is made of solid wood, probably cherry-tree, and is in good condition. It has delicate dovetail joints, solid and decorative. The finish is somewhat worn but it is easy to restore. The box keeps the leather strip to carry the instrument, and also the original iron shutting hooks. As stated before, inside the cover there is a paper label with the operating instructions printed on it. This vibrograph is surely a striking historical surveying instrument, made by a prestigious brand and that has come to our days with all the charm of vintage scientific antiques. Measurements: 240 mm width x 415 mm height.