The trough of the aquaduct could rest on the center and top of the arch, the keystone (red in the models). From there, the downward vertical force is modified partly into outward horizontal force, and ...

The keystone is the most important component of an arch. However, it is also the component that endures no stress — and, typically, responsibility and stress go hand in hand. A keystone is the ...

A keystone in an arch's crown secures the other stones in place. Keystone species play the same role in many ecological communities by maintaining the structure and integrity of the community.

The nonprofit volunteer organization dedicated to increasing public awareness and appreciation of the Quabbin Reservoir and ...

The term "keystone" resonates with a profound array of meanings across diverse domains, embodying critical elements in ...

David Cameron will describe US support for Ukraine as the “keystone in the arch” of the fight for democracy in his latest appeal to Congress over a stalled package of aid. The Foreign ...