Beer pump clip
A beer engine is a device for pumping beer from a cask in a pub's cellar.
The beer engine was invented by John Lofting, a Dutch inventor, merchant and manufacturer who moved from Amsterdam to London in about 1688 and patented a number of inventions including a fire hose and engine for extinguishing fires and a thimble knurling machine. The London Gazette of 17 March 1691 stated "the patentee hath also projected a very useful engine for starting of beers and other liquors which will deliver from 20 to 30 barrels an hour which are completely fixed with brass joints and screws at reasonable rates."
The locksmith and hydraulic engineer Joseph Bramah developed beer pumping further in 1797.
The beer engine is normally manually operated, although electrically powered and gas powered pumps are occasionally used; when manually powered, the term handpump is often used to refer to both the pump and the associated handle.
The beer engine is normally located below the bar with the visible handle being used to draw the beer through a flexible tube to the spout, below which the glass is placed. Modern hand pumps may clamp onto the edge of the bar or be mounted on the top of the bar.
A pump clip is usually attached to the handle by a spring clip giving the name and sometimes the brewery, beer type and alcoholic strength of the beer being served through that handpump.
The handle of a handpump is often used as a symbol of cask ale. Keg beer dispensers usually feature illuminated countertop fittings behind which a handle opens a valve that allows the gas pressure in the keg to force beer to the attached spout.
A swan neck is a curved spout. This is often used in conjunction with a sparkler - a nozzle containing small holes - fitted to the spout to aerate the beer as it enters the glass, giving a frothier head; this presentation style is more popular in the North of England than in the South.
A sparkler is a device that can be attached to the nozzle of a beer engine. Designed rather like a shower-head, beer dispensed through a sparkler becomes aerated and frothy which results in a noticeable head. Some CO2 is carried into the head, resulting in a softer, sweeter flavour due to the loss of normal CO2 acidity.
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