For both technical drawing and art for pleasure's sake, artists utilized a range of drawing instruments in the 18th century. Some of these instruments had only recently appeared, while others were based on older designs still useful in the 18th century. Dedicated artisans often carried around cases containing these instruments; by the 18th century, such cases were typically relatively large.
Two rulers of the same length connected by a hinge, sectors were utilized in drawing during the 18th century and up until the 19th century, when they were effectively replaced by the slide rule. The sector was a regular in the drawing sets that became popular in the 18th century. Each sector contained three varieties of scale, including the sectoral scale for calculations, the rule for measuring lengths and the plane scale for tangents and logarithms.
Pencils in the 18th century were often constructed of graphite. This material became used in the production of this instrument after a huge graphite deposit was discovered in England in the 16th century. While the graphite pencil left a more substantial --- and thus useful for drawing --- mark on the paper than lead, it was also more inclined to snap and so artists used holders for their graphite pencils.
Utilized to draw circles or arcs in a precise manner, compasses in the 18th century included triangular models. These featured three arms rather than two and so allowed the artisan to transfer three points from a drawing at once, increasing the device's utility. Compasses were constructed of metals and expensive models would be made from ornate steel.
A proportional divider resembles a pair of scissors, except that each end features a point. The divider can also be adjusted via a movable joint, allowing the user to configure the transfer ratio of the instrument. The idea behind the proportional divider was to allow an artisan to discern correctly the proportions of a subject, increasing the accuracy of a drawing. Proportional dividers were predominantly used from the 18th to the 20th centuries.
Rulers came in a number of varieties even in the 18th century. Some were akin to the basic rulers commonly found in school classrooms in the 21st century, used for measuring small distances, except that in the 18th century such instruments were constructed out of materials such as ivory. These ivory rulers featured diagonal scales on one side, and were small enough to be included in pocket-sized sets of instruments. Parallel rulers, consisting of two straight rules connected by two metal arms, gained prominence among artisans in the 18th century. The ruler's arms could be used to adjust how far away each rule was from its partner.
- Museum of the History of Science, Oxford; Epact; Drawing Instruments; Stephen Johnson
- Maths Instruments.me.uk: Sectors For Calculation
- Pencils.com; Pencil History; 2010
- Gilai.com: 18th Century French Triangular Compass
- Explore Drawing and Painting.com: Discover these Four Tools For Creating A Realistic Drawing
- Maths Instruments.me.uk: Proportional Dividers: A Selection
- Comstock/Comstock/Getty Images