Time and Weather Instruments
For many years we at Time and Weather Instruments have grown to become outstanding providers of a wide variety in alarm clocks, clock mechanism and clock movement throughout the whole of the UK. We provide our competitively prices clocks for retail and wholesale establishments, which can be deliver to anywhere in the UK along with shipping to the EU. Throughout our website you will find a wide range of clocks from bathroom, desk and outside clocks to wall, caravan, boat and digital clocks.
Fortin Barometer - With Torricellis barometer all readings are taken from the surface level in the bowel to the height of mercury in the column. However this means using a moving scale to find the height at the top of the scale. The Fortin barometer overcomes this problem by using an adjustable container or cistern so that the open mercury level can be raised or lowered to a fixed point. The column height is then measured with a fixed vertical scale, Sometimes an adjustable vernier scale is added to the Fortin barometer which allows for far more accurate readings to be taken.
Kew Barometer - These barometers are designed to be portable and are often used on ships. The effect of motion is overcome by introducing a restriction in the column, which dampens such oscillations without unduly affecting the sensitivity of the barometer.
Aneroid Barometers - The aneroid barometer was invented by the Italian Lucius Vidi in 1843. The term aneroid' means without liquid. The principle of the aneroid barometer is that a sealed metal chamber, sometimes called the bellows or diaphragm, expands and contracts with changes in the atmospheric pressure. This expansion and contraction is recorded and its result amplified and indicated by means of a pointer on a scale.
Aneroid Barograph - A refinement to the aneroid barometer whereas a pen replaces the pointer and traces the readings onto a graph or chart which is placed onto a slowly revolving drum. Because of the friction between the pen and the paper its accuracy is not quite as good as the aneroid barometer. For better sensitivity, a refined version Known as a microbarograph is used. In this device the graph is to a much larger scale.