Home / Brinton, Willard C. Graphic Methods for Presenting Facts. New York: The Engineering Magazine Company, 1914. Internet Archive identifier: cu31924032626792 (Cornell University Library copy). The first American textbook on what we now call data visualization. / Passage

Graphic Methods for Presenting Facts

Brinton, Willard C. Graphic Methods for Presenting Facts. New York: The Engineering Magazine Company, 1914. Internet Archive identifier: cu31924032626792 (Cornell University Library copy). The first American textbook on what we now call data visualization. 294 words

In Fig. 212 we have complete in black ink the same card which in Fig. 206 is given full scale, using two colors to make the contrast between the green-ink background and the black-ink curve. Though Fig. 212 shows the card in reduced size, it nevertheless gives a very good idea of the appearance of a card suitable for the plotting of records for one year by weeks, making it necessary to have fifty-two entries of figures in the upper part of the card.

In Fig. 212 the arrangement to show the dates along the bottom of the card, with short vertical lines dividing the horizontal scale into months, is not put on to the card until the exact year is known for which the particular card is to be used. Lines dividing the year into months so as to show exactly how many weeks are included in each month and at just which portion of the week the beginning or end of each month may occur are then put in by hand. In Fig. 212 the card has been used for a fiscal year beginning August 1. The card is marked 1911, meaning the fiscal year ending July 31, 1911. By referring to the calendar for the year 1911 one may see how the short lines for months are put in. As the pay weeks ended on Thursday, there were only four pay weeks ending in July, but there were five pay weeks ending in March. March 1 came on Wednesday. The last day of March was on Friday. The vertical co-ordinate lines for March show clearly that there were five Thursdays, and they also show the exact time relation of the Thursdays to the beginning and to the end of the month.