Images

A meadow on Lower Culp's Hill, one of the battle sites at Gettysburg Battlefield.

A view of Big Round Top and the Gettysburg National Military Park visitor center from the Culp's Hill observatory tower, one of the battle sites at Gettysburg Battlefield.

Coal was essential to the operation of the larger steam engines. Coal burns at extremely hot temperatures and burns for a long time, making it an ideal fuel for converting water into steam.

A sand storage silo at Steamtown National Historic Site. Sand was stored in a dome on top of the engine and, as the train traveled the tracks, the sand would be sprinkled down pipes to land on the tracks in front of the wheels. This would aid the wheels in gripping the tracks, especially when the rails were wet.

A sand storage silo at Steamtown National Historic Site. Sand was stored in a dome on top of the engine and, as the train traveled the tracks, the sand would be sprinkled down pipes to land on the tracks in front of the wheels. This would aid the wheels in gripping the tracks, especially when the rails were wet.

Petroleum first saw widespread use in the transporation industry as a lubricant. It was refined into various products depending on which part of the engine they were meant to lubricate. Once transported by tanker car, it was stored in large tanks such as this one.

A panorama of fall colors from the observatory tower at Culp's Hill, one of the battle sites at Gettysburg Battlefield.

A meadow located at the foot of Culp's Hill, one of the battle sites at Gettysburg Battlefield.

A copse of trees at the base of Culp's Hill, one of the battle sites at Gettysburg Battlefield.

Visitors at Glines Canyon East Abutment in Olympic National Park, the location of the Elwha River Restoration project. Image available at Olympic National Park flickr site.

An endangered black-footed ferret is released on private land in Arizona as part of a collaborative species recovery effort.

Jet ski in fotsam at Salt Creek at Greenwood, NE.

Female pallid sturgeon captured in the Missouri River near Boonville, MO. 

A Whooping crane chick is released into a temporary pen to acclimate before being released into the wild.  Four of the endangered chicks, hatched and raised by their parents at the U.S. Geological Survey’s Patuxent Wildlife Research Center in Laurel, Maryland, were released on Necedah National Wildlife Refuge in Wisconsin.  

USGS scientists J. Alton Anderson and Carole D. Johnson prepare to collect a Nuclear Magnetic Resonance (NMR) log at a well. 

USGS scientist, Mark Reid, in front of the exact place where the main body of the landslide, composed of glacial lacustrine clay, overrode the liquified alluvium of the river valley.

Coral growth offshore of the Hawaiian Island of Kahoʻolawe has been significantly impacted by the island's deforestation and resulting erosion and sediment run-off into the nearshore environment. This image is of a coral reef in deeper waters offshore of Kahoʻolawe.

A juvenile common loon wearing a satellite transmitter antenna follows an adult.

Increased flow over rock riffle in Sonoma Creek seen after South Napa Earthquake of August 24, 2014.

Location: Sonoma Creek downstream of the Agua Caliente Road Bridge, Sonoma County, California.

Colonies of “blade fire coral” that have lost their symbiotic algae, or “bleached,” on a reef off of Islamorada, Florida. Hard and soft corals are presently bleaching- losing their symbiotic algae – all over the coral reefs of the Florida Keys due to unusually warm ocean temperatures this summer.

No, that is not a mound of snow sitting on a coral reef – it is a colony of bleached "brain coral" on a reef off of Islamorada, Florida. Hard and soft corals are presently bleaching- losing their symbiotic algae – all over the coral reefs of the Florida Keys due to unusually warm ocean temperatures this summer.