Hygrometer
![ADV_ hygrometer_hero](/sites/default/files/styles/container_width_large_x1/public/ADV_%20hygrometer_hero.jpg?itok=sdqSWsoF)
As an artist and observer of the science of nature da Vinci was fascinated by the sky and sketched his observations of changes in the atmosphere.
His hygrometer is based on a simple balance scale. When dry the cotton and the weight opposite are in balance. As the cotton absorbs atmospheric moisture it grows heavier indicating an increase in humidity.
![ADV_ hygrometer_2](/sites/default/files/styles/container_width_large_x1/public/ADV_hygrometer.jpg?itok=LNv9gyYL)
![ADV_ hygrometer_1](/sites/default/files/styles/container_width_large_x1/public/ADV_hygrometer_small.jpg?itok=Qj7LfO4t)
IMAGE: Hygrometer Photo: Vitaly Korovin / Shutterstock.com
Hygrometer
brass, Perspex, wadding and metal