>I wonder often what people with bad vision did before glasses were readily available.

Before the invention of glasses, people with bad vision had limited options for correcting their eyesight. Here are some historical methods that were used:

• Squinting: Some people with mild to moderate myopia (near-sightedness) could compensate for their blurred distance vision by squinting, which temporarily improves the focus of the eye.
• Using Magnifying Glasses: Magnifying glasses have been around since the 13th century, and they were sometimes used as a crude form of corrective lenses by people with presbyopia (age-related farsightedness). They could also be used for specific tasks, such as reading small print.
• Improvised Lenses: In ancient Rome, the philosopher Seneca reportedly used a glass globe filled with water to magnify text. Later on, in the Middle Ages, people would sometimes use convex or concave gems or crystals to create makeshift lenses.
• Seeking Help from Others: People with poor eyesight may have relied on others to read and write for them or to guide them around. This could include family members, servants, or professional scribes.