Wet or dry, green or shiny or black, coming from France or Germany…many people confuse them with clocks, others with explosives; however they are the gas meters. What did they do? They measured the quantity of gas that was consumed by domestic or industrial customers. There were also wet weters, which operated with water and were particularly accurate. Due to the fact that the water would evaporate in higher temperatures or freeze at lower temperatures, the water was eventually replaced with oil. On the other hand, the dry meters did not have the same problems but they were not as accurate. The coal gas drastically changed the everyday life, as it relieved the housewives from the use of coal and its smoke, based on advertisements of that time. During the 1930s, the introduction of electricity slowed down the rise of the coal gas and eventually replaced it.