“Drogo
11-09-2013, 02:03 PM
Appeared in the Spectator Jan. 28, 1881
THE BURLINGTON CANAL
Incidents Attending Its Construction
(Written for the Spectator)
The building of the Burlington Canal was a big event, and the inquisitive inhabitants for many miles round about, as curiosity or Business called them, did not lose an opportunity of watching the progress of the work. Small spritsail boats and bateaux had passed occasionally through the natural outlet from the bay, when the mouth was not closed up with sand by easterly storms: but when an artificial passage through the beach was contemplated it was considered the eighth wonder of the world. How was it possible for so great a work to be accomplished? How was the drifting sand to be kept in check, (or how could it be dug out?) At all small gatherings of the people-at bees and visiting parties the subject was discussed; neighbourhood dispute and gossip were forgotten in the presence of this great enterprise; the general opinion being that it must end in disappointment. Why, the beach was all sand, the accumulation of the and blown material brought thither by easterly storms during centuries past, which, being deposited at first as a bar, had in the end risen above the surface; and as no westerly blows could disturb it, or carry it away, the result was the present ever widening beach.” …
“CON'T
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Drogo
11-09-2013, 02:03 PM
… “The commencement of the work was very simple; wagons and carts were used to remove the sand above the water level; then a huge scow with gearing driven by relays of four horses, scooped up the sand by means of endless chains revolving on drums, to which buckets were attached in such a way that, on rising to a certain height they cast their contents into false-bottomed scows, which, alternately were loaded and discharged their burden in deep water in the bay. When a sufficiently large opening was made, cribs of timber only twelve feet in width were (sunk) and filled with stones gathered along the shore of the lake.”
The problem that was being alluded to here, is that unlike digging a trench in clay conndissions, where the sides of the trench remain intact, when digging in sandy condisions, the sand collapses.
So how then was the canal cut through the sand bar? The answer might lie in the sentence, “When a sufficiently large opening was made, cribs of timber only twelve feet in width were (sunk) and filled with stones gathered along the shore of the lake.”
My reading of this is, that before any digging began, two cribs were constructed on the beach, from the lake to the bay, one where the north bank of the canal was intended to be located, and one where the south side was intended to be. And then the cribs were ‘sunk’ or driven down in to the sand, probably with the use of an animle pile driver. In this way, as the cut through the sand bar was being made, the cribs would prevent the sand on the outersides of the cribs from collapsing.
PILE DRIVER
“A pile driver is a mechanical device used to drive piles (poles) into soil to provide foundation support for buildings or other structures.”
“One traditional type of pile driver includes a heavy weight placed between guides so that it is able to freely slide up and down in a single line. It is placed upon a pile. The weight is raised, which may involve the use of hydraulics, steam, diesel, or manual labour. When the weight reaches its highest point it is then released and smashes on to the pile in order to drive it into the ground.”
“Ancient pile driving equipment used manual or animal labor to lift heavy weights, usually by means of pulleys, to drop the weight onto the end of the pile.”
http://en.wikipedia.org/wiki/Pile_driver#History
so in the case of the Burlington Canal, maybe the cribs along each side, were built in short sections, and then individually driven down in to the sand by a pile driver. Perhaps planks were placed across the centre of each crib, and the pile driver weight was then dropped on the planks.
where the sides of the canal were intended to be located.