For sale, an Edwardian period Snowdon Pattern copper rain gauge by Negretti & Zambra of London.
This simple yet effective instrument has been known as the standard for rainfall measurement since the 1860’s when the British Rainfall Organisation led by GJ Symons trialled a number of available instruments. According to Negretti & Zambra’s catalogues of the 1870’s this instrument was considered an improvement to the Howard’s rain gauge which consisted of a glass bottle with a funnel placed in the top. This earlier example was proven to be hugely vulnerable to failure in cold weather due to the exposed nature of the glass and the effects of freezing temperatures upon it.
To counteract this issue, Symons suggested that the glass bottle should be contained within a copper can which was to be partially buried in the earth to avoid surface temperatures on the glass, to maintain a level position and also to collect any spillage during extreme rain events. The cylindrical copper lid contains a funnel at the base with a tube that protrudes down into the glass measuring cylinder and the high surrounding sides were intended to reduce the amount of in-splash or out-splash associated with the landing of the raindrops and equally to allow for the collection of snowfall. Furthermore, the rim was surrounded by a piece of brass with a sharp knife edge lip to ensure that the catchment area remained as defined as possible.
This example comes unusually complete with its original glass cylinder and internal copper bucket for lifting the cylinder out of the can for measurement. A fine example with original Negretti & Zambra brass plaque to the front and owing to the style of the trade mark logo, likely to date to around 1910.
Negretti & Zambra were a leading name in the production of meteorological and scientific instruments and had a company history dating back to 1850 although their parents were amongst those Italian emigres that bolstered the British meteorological instrument making industry at the turn of the century.
Throughout their long and esteemed history they exhibited at British and international industrial fairs and became makers to both Queen Victoria and Edward VII. Owing to changes in the business, the firm ceased the public retailing of scientific instruments sometime around the late 1960’s and continued with a focus on the aviation industry in numerous guises until its eventual liquidation in the year 2000. They are today perhaps the most collected of the scientific instrument firms which bears testament to the quality of their work.