The cause of CFS if unknown. A large portion of cases are triggered by an infection and some by trauma. Stress is also present at the onset in almost all cases. Some people believe that CFS is caused by an agent entering the body, while others think it is due to the body's response, possibly to various agents.
The first formal committee of correspondence was established in Boston in 1764 and was charged with rallying opposition to the recently enacted Currency Act and the unpopular reforms imposed on the customs service.
The Ottoman Ministry of Post was established in Istanbul on 23 October 1840. The first post office was the Postahane-i Amire near the courtyard of the Yeni Mosque. In 1876 the first international mailing network between Istanbul and the lands beyond the vast Ottoman Empire was established.