This page needs to be proofread.
 | An image should appear at this position in the text. To use the entire page scan as a placeholder, edit this page and replace "{{missing image}}" with "{{raw image|Graphic methods for presenting facts (1914).djvu/76}}". Otherwise, if you are able to provide the image then please do so. For guidance, see Wikisource:Image guidelines and Help:Adding images. |  |
Fig. 59. Chart Showing the Operation of Some Freight Lighters in New York Harbor
Each horizontal bar represents one lighter. Night hours from six to six are shown by the gray vertical areas. Colored crayons used on the original chart made the information stand out much more plainly than possible here with black ink only
