Block · one region of the page, as the scanner read it. It may hold a whole story, part of one, several, or an advertisement; stitching blocks into articles is the next step. Text is supplied OCR.
Page 4 · column 3 of 7 · from the scan, no model involved
First go to the library and read the article on acid rain in the August issue of Popular Science. Note that the map does not include much below Washington, D.C.
Next, read the article in May/June issue of Sierra Magazine, paying special attention to insert on page 52^ showing the pH Scale. Use one of the
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