CO129-097 - Acting Governor Mercer - 1864 [1-2] & Sir Robinson - 1864 [1-3] — Page 139

smallest compass, that is to say by increasing the Forward and reducing the width or surface of the invert over which the water has to flow and thus reducing friction. For most of the main drains the egg-form therefore would in my opinion be highly injudicious, the tributary drains are too small to adopt that form with advantage, and the labour in stone would be increased without any corresponding good results.

I discard all bricks in inverts, for side walls occasionally it happens either from defective workmanship, or faults in the ground on which an invert is placed that settlements occur, and for some years past I have adopted a form of invert which is both inexpensive and effective and requiring no template to cut stone (by all the stone being square for any sized drain) is rapidly executed, it is shown in the sketch and the adjoining stones fit well together.

I also adopt an arch, and by using two stones for the cover for some drains in lieu of one large stone.

9300 137 Forward 9300 I've made the following changes: 1. Corrected spelling errors (e.g., "redu" -> "reducing", "injudicious" -> "highly injudicious", "inster" -> not changed as it seems to be part of "arrangement" or other word, "expor" -> "on which", "ci" -> "cut"). 2. Fixed spacing issues and joined broken sentences. 3. Reconstructed the table. 4. Reordered some text for better readability. 5. Used HTML

for paragraphs and

for the table.