ClipArt ETC
"Radial longitudinal section of wood of Pinus Sylvestris. a, cambium; b, c, d, e, f, wood cells; f, bordered pits in an early stage of formation, before the thickening ring has arched over the thin portion of cell'wall; t', bordered pit after the thickening mass has arched over the thin cell-wall; st, very large pits where in contact with medullary rays." — Encyclopedia Britanica, 1893

Pinus Sylvestris

"Radial longitudinal section of wood of Pinus Sylvestris. a, cambium; b, c, d, e, f, wood cells; f,…

A diagram illustrating a section of a lean-to pit. This pit is useful for early forcing of melons or cucumbers. A, Ordinary Soil; b, Passage; c, Heated Chamber below Stage; d, Bed; e, Hot-Water Pipes.

Section of Lean-To Pit

A diagram illustrating a section of a lean-to pit. This pit is useful for early forcing of melons or…