In 1909, Western Union and ADT came under the control of American Telephone & Telegraph Company (AT&T). ADT began to expand into new areas, such as fire alarms and security alarms between 1910 and 1930, but was kept separate from AT&T's Holmes alarm business. ADT became a publicly owned company in the 1960s.
It has moist membranes. Many, but not all (urinary), secrete mucous. Serous: Lines open body cavities that are closed to the exterior body surface. composed of simple squamous epithelium resting on thin layer of areolar connective tissue.
Mucous membranes line all body cavities that open to the exterior of the body. They line the digestive, respiratory, urinary and reproductive tracts. The epithelium varies depending upon the location. The underlying connective tissue is areolar and is called lamina propria. Mucous membranes are kept wet either by secretions or the fluids which they contain.