College in Geneva (1857-1859). Studies of medicine in Montpellier, Paris and Würzburg (doctorate in 1867). Professor in Würzburg. Named with the academy of Lausanne, Forel teaches there the anatomy and general physiology (since 1871), the zoology and the comparative anatomy (since 1875). It gives up its courses in 1895 to be delivered to the only research. To advise communal (legislature) in Morges (1867-1909), appointed liberal with the Great Council of Vaud (1870-1874).

Initiated by his/her father, Forel is interested very young person in the lake Léman. It multiplies the original observations, gathering the data on lake fauna and the flora, sticking to studies of hydrology, climatology, meteorology, physical geography, history.

It publishes Léman, vast and remarkable monograph in three large volumes published in 1892.1896 and 1904 (republication, 1969 and 1998). This work, internationally recognized, makes of Forel the founder of limnology, science of which it creates also the name.

Its discoveries relating to the life of the lakes, their physical and chemical characteristics, are innumerable. He is worried for example diseases of fish and contributes to the development of Swiss pisciculture. He studies the tides and the cuttlefish, the currents and the waves, the transparency and the colors of water.

Towards the end of its life, Forel takes again the searchs for his/her father on the lake stations and becomes one of the best specialists in the Bronze Age in Switzerland. Precursor of seismology, it is the first with launching sounding-balloons for meteorological observations in upper atmosphere. The study of the lakes involves it to undertake that of the glaciers (annual observations). It chairs the very new Swiss glaciologic Commission (1894) and organizes a subscription to finance a Swiss forwarding in Greenland (1912), which gives its name to a mountain of the island.