The challenge facing the signal industry was achieving the same level of safety and reliability that was inherent to purely mechanical systems. An experimental hydro-pneumatic interlocking was installed at the Bound Brook, New Jersey junction of the Philadelphia and Reading Railroad and the Lehigh Valley Railroad in 1884.
This is an example of an expository paragraph   In 1997, 175,000 volunteers picked up three million pounds of garbage along the coasts of the United States. As a result, bo â¦ th people and sea animals can enjoy cleaner and safer environments.
An expository essay is a piece of writing where the writer presents opinions, points of view, ideas, concepts, arguments on a... particular topic. It is usually a formal piece of writing with an introduction, a discussion, and a conclusion.