 | David Stevenson - 1872 - 412 páginas
...grooves formed at those narrow parts of the canal which occur under road bridges, or at contractions made at intermediate points to receive them. Self-acting...reach, when the repairs can be made, and the water afterwards restored, with comparatively little interruption to the traffic. Their value in obviating... | |
 | 1910 - 1032 páginas
...slipped into grooves formed at the narrow points of the canal under road bridges, or at contractions made at intermediate points to receive them. Self-acting stop-gates have been tried, but have not proved trustworthy. When repairs have to be made stop-gates allow of the water being run off... | |
 | Hugh Chisholm - 1911 - 1032 páginas
...slipped into grooves formed at the narrow points of the canal under road bridges, or at contractions made at intermediate points to receive them. Self-acting stop-gates have been tried, but have not proved trustworthy. When repairs have to be made stop-gates allow of the water being run off... | |
| |
In small works they may be made of thick planks, which are slipped into grooves formed at those narrow parts of the canal which occur under road bridges, or at contractions made at intermediate points to receive them. Self-acting stop-gates have been... 