H. Chapin (Herman Chapin) was a well-known 19th-century American toolmaker, especially recognized for his high-quality wooden measuring tools, including folding rules. His company, H. Chapin & Sons, was established in Pine Meadow, Connecticut, around 1828, and became one of the most respected names in the industry.

**Chapin Rules:**

1. **Materials**: Chapin rules were commonly made from boxwood, chosen for its durability, stability, and fine grain, which made it ideal for precision tools. Brass or German silver fittings were often used to reinforce the joints and ends for added strength.

2. **Design**: H. Chapin’s rules were well-known for their attention to detail. They were typically four-fold or two-fold wooden rules with brass hinges. The graduations were finely marked and often engraved, ensuring long-lasting accuracy. Some of the rules also included caliper ends for precise internal measurements.

3. **Markings**: Chapin rules came with both imperial and metric markings, depending on the version, and were noted for their readability and precise graduations.

4. **Innovations**: Chapin also made combination rules and folding rulers that incorporated calipers and other measuring functions, making them versatile tools for woodworkers, carpenters, and engineers.

5. **Partnership with Stephens**: In 1866, H. Chapin merged with the J. R. Stephens company, a maker of similar measuring tools. This partnership produced the “Chapin-Stephens” branded rules, which became famous for their superior craftsmanship and accuracy. The brand remained influential well into the 20th century.