Hollander Beater,
Hollander Beater is a mechanism invented in 17th century Holland to enable the mixing of pulp, and though there are more chemical ways of breaking down materials Hollanders are still commonly used. There are variations of this yet all have an oblong trough with rounded ends in which water and the base material being beated circulate, a rotating cylinder with dull metal blades (known as the roll) and a bed plate of raised dull metal blades in the bottom on the trough.

Hookah,
The hubble-hubble, a smoking pipe which draws tobacco fumes from leaves placed over a clay burning charcoal holder.

Horizon line,
Actual or imaginary line in a work of art representing the point at which water or land seems to end and the sky begins.  

Hot Press paper,
Hot Press paper 'smooth, even surface type that is ideal for fine detail work with pen and ink'.

Hue,
Another word for color, such as red, yellow, or green.  

Hukka,
Contraption for smoking tobacco. It consists of a bowl, a long flexible tube and a base containing water that cools and filters the smoke

Huqqa /hookah,
A water-pipe, Rajasthan

Hutusilli,
Pipe of the Nishi tribe from Arunachal Pradesh