| 摘要 |
<p>The tunnel cloche comprises a sheet of plastic film stretched over a framework of semi-circular rigid wires. The ends of these are located in holes positioned in a flat base frame. The structure can easily be dismantled for storage and positioned regardless of ground conditions. The base frame has two rigid rails (a) forming the long sides of the cloche. Their separation is adjusted and maintained by a rod (b) at each end. Positioning holes are provided at regular intervals, these permitting the use of one single frame (f), or two adjoining frames (g).</p> |
