A jumbo is a mobile drill carriage or scaffold on which several drills could be mounted. This image may depict the construction of tunnels for New York City's water supply from the Catskill watershed. In 1905 the New York State legislature passed an act allowing the City to acquire lands and build water control structures in the Catskills for its water supply, including the East Delaware Tunnel, West Delaware Tunnel and the Rondout Tunnel (Delaware Aqueduct).
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The export option will allow you to export the current search results of the entered query to a file. Different
formats are available for download. To export the items, click on the button corresponding with the preferred download format.
By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.
To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export.
The amount of items that can be exported at once is similarly restricted as the full export.
After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.