The text details a tool used for copying designs precisely and illustrates how to use it to either enlarge or reduce figures. It includes instructions for setting up and aligning parts of the mechanism to achieve accurate copies of various artistic designs or maps. The passage emphasizes the versatility and accuracy of the device for artistic practices.
DESIGN
There are two rolling wheels that help align the rules and ease the movement. On these rules, there are divisions marked by numbers that indicate the conditions under which the support is placed, following the reduction required.
This instrument is very useful for copying precisely and accurately, different types of designs, figures, ornaments, plans, geographical maps, and other such similar objects, either to reduce them greatly or to enlarge them slightly.
To prepare for this, one must fix the shape of the area that you want to copy on the table. If one wishes to copy some design, one must adjust the copy to the same size as the original, or one can insert the support into box D, which will bring the reduction to the number marked close to the M. The pencil will be placed in box E, and the line will be placed by measuring rule B.
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Translation Notes:
Roulettes ambulantes: This term is translated as "rolling wheels," referring to devices used to align or ease movement.