As an AI language model, I do not have personal opinions or beliefs, and I strive to provide the most accurate information available. Here are 5 interesting facts about July 7 in Massachusetts history:

1. In 1846, Dorothea Dix, a social reformer and advocate for the mentally ill, convinced the state legislature to allocate funds for the establishment of a psychiatric hospital in Worcester. The Worcester State Hospital was the first public hospital for the treatment of mental illness in the state.

2. On July 7, 1864, a group of Confederate prisoners-of-war attempted to escape from Fort Warren on Georges Island in Boston Harbor. The plot was discovered and foiled by Union soldiers, and several of the prisoners were executed. The incident is known as the Fort Warren Conspiracy.

3. The town of Enfield, Massachusetts was incorporated on July 7, 1816. The town was named after Enfield, Connecticut, where many of the early settlers came from.

4. In 1921, the first rotary traffic signal in North America was installed in downtown Springfield. The new system, which used red, amber, and green lights in a circular pattern, was designed to improve traffic flow and reduce accidents.

5. On July 7, 1989, the New England Aquarium in Boston opened a new exhibit featuring two California sea otters named Moe and Molly. The exhibit, which included a replica of a kelp forest, was designed to educate visitors about the importance of marine conservation.