Osa-ranma

What an osa-ranma is

An osa-ranma is a Ranma filled with fine vertical bars set close together. The Japanese name compares them to the reed of a loom, through whose narrow slots the warp threads pass. Unlike a carved transom, it composes its surface from repeated lines alone.

Formal reception rooms use it. The Tomita Residence in Ibaraki Prefecture, from the early Meiji period, is described as having a large Doma and living room to the north and three Zashiki ranged to the south beyond an entrance room, the innermost projecting as a wing, and its Kugikakushi bearing the crest of the domain lord together with transoms of this kind mark it as a formal Shoin-zukuri interior.

Gates carry them above the doors. The front gate of the Nakamura Residence in Kyoto Prefecture, from the early Showa period, has double boarded doors with one of these transoms above them, in what the entry calls a small but carefully made gate.

So do castle entrances. The entrance at Matsuyama Castle in Ehime Prefecture, reconstructed in 1967, has an open Shikidai without side walls, a Kaerumata on the Kōryō above the front columns and one of these transoms in the wall above, which the entry judges fitting for the entrance to a Tenshu.

Recognising it

The gauge and spacing of the bars give it away. Vertical members set too close to admit a finger identify this type, and the direction and density of the lines distinguish it from pierced or bamboo-node transoms.

It passes light and air while blocking the view. Between rooms it conveys only a sense of movement next door; above a gate door it admits only the brightness outside.

Records usually name the kind of transom rather than leaving it general. The reed, bamboo-node and pierced types are distinct designs, so a quotation should carry the kind across.