Transcriber's Notes:
Obvious spelling and punctuation errors were repaired. Period spellings were retained (for example: orchestres, etc.), along with valid alternate spellings of the same word. "Stationary" is used for "stationery" consistently in this text. Retained.
There were several words that the original included in both hyphenated and non-hyphenated forms; these were retained.
Heading punctuation and formatting, which varied in the original, has been standardized.
Illustrations on P. 63 (Printer), 73 (Type-founder), and 81 (Paper- maker) have no captions in the original.
P. 66, "Durandi Ralionale divinorum officiorum" in the original is the official title in several sources. Retained "Ralionale" spelling.
Changes not covered by notes above were:
P. 10, "now became clefs"; original reads "clifs."
P. 159, "convex drawing-knife"; original reads "onvex."