hygromètre de Regnault

Désignations

Codes : pays ou zone où la désignation a cours (CH, FR, DE, EU = Union européenne, INT = usage international). Une désignation barrée est déconseillée.

Définitions

français

Hygromètre à point de rosée mis au point par le physicien français Henri Victor Regnault.

anglais

Regnault devised a hygrometer of the dew-point type consisting of two silver vessels A and G (see diagram), mounted side by side. Air may be blown from D through a tube C dipping into ether contained in A. This causes the ether to evaporate through E thus cooling the tube A until eventually, at the dew point, moisture condenses on the outside of A giving it a dull appearance compared with the surface of G. This temperature, and that at which the dullness disappears on allowing the apparatus to stand, are noted on the thermometer F, the mean giving the dew point, which in conjunction with the room temperature, enables the relative humidity of the air to be calculated.