Pennsylvania Photos

Surgical Amphitheatre

Science Photo Library

Lewis And Clark Expedition Diary

Science Photo Library

Lise Meitner With Students

Science Photo Library

Nuclear Power Station #2

Science Photo Library

Benjamin Franklin Parkway Plans

Science Photo Library

Pennsylvania Oil Rush

Science Photo Library

Pennsylvania Oil Rush #1

Science Photo Library

Pennsylvania Oil Rush

Science Photo Library

Franklin's Lightning Experiment

Science Photo Library

William Osler Teaching Medicine

Science Photo Library

Escalator

Science Photo Library

Railway Oil Transportation

Science Photo Library

Rutile Specimen

Science Photo Library

First Aircraft Landing On A Ship

Science Photo Library

Strontianite And Calcite

Science Photo Library

Trees In Autumn

Science Photo Library

Effects Of Zinc Smelting

Science Photo Library

Onions On Lorry

Science Photo Library

First World War Munitions Factory

Science Photo Library

William Proctor

Science Photo Library

Longwood Gardens

Science Photo Library

Traffic Jam #1

Science Photo Library

Allegheny Reservoir

Science Photo Library

Lewis And Clark Expedition Journals

Science Photo Library

Natural Gas Pipeline Marker At Sunset

Science Photo Library

Iron Works #1

Science Photo Library

First Oil Well In The Usa

Science Photo Library

Anatomy Lecture And Dissection

Science Photo Library

Eugene Ely Taking Off From Uss Pennsylvania

Science Photo Library

Heinz Ketchup

Science Photo Library

Eugene Ely Taking Off From Uss Pennsylvania #2

Science Photo Library

Eugene Ely Taking Off From Uss Pennsylvania #1

Science Photo Library

Fracking Drill Rig

Science Photo Library

Solar System Diagram

Science Photo Library

Bull Frog

Science Photo Library

Lewis And Clark Expedition Journals #1

Science Photo Library

Lewis David Von Schweinitz

Science Photo Library

Philadelphia

Science Photo Library

Schultz House After Johnstown Flood

Science Photo Library

Museum Guide Robot

Science Photo Library

Washington Dc In Snow

Science Photo Library

Burkburnett Oil Field

Science Photo Library

Philadelphia

Science Photo Library

Pennsylvania Farm

Science Photo Library

Pennsylvania Farm #1

Science Photo Library

Natural Gas Well

Science Photo Library

Miners Rally Against Coal Burning Limits

Science Photo Library

Rally To Support Coal Burning Limits

Science Photo Library

Rally To Support Coal Burning Limits #1

Science Photo Library

Blast Furnace

Science Photo Library

Industrial Truck Operator

Science Photo Library

Blast Furnace #3

Science Photo Library

Blast Furnace #4

Science Photo Library

Blast Furnace #5

Science Photo Library

M. Carey Thomas

Science Photo Library

Peter Lesley

Science Photo Library

Motor Vehicles At A Scrapyard

Science Photo Library

Industrial Machine Operator

Science Photo Library

Ultrasharp Silicon Carbide Tip

Science Photo Library

Blast Furnace #6

Science Photo Library

Gotthilf Henry Muhlenberg

Science Photo Library

Gas Pipeline Construction

Science Photo Library

Natural Gas Pipeline Marker At Sunset #1

Science Photo Library

Franklin In His Laboratory

Science Photo Library

Motor Vehicles At A Scrapyard #1

Science Photo Library

J. Russell Smith

Science Photo Library

Motor Vehicles At A Scrapyard #2

Science Photo Library

Wind Turbines In Winter

Science Photo Library

Gas Pipeline Construction #1

Science Photo Library

Blast Furnace #10

Science Photo Library

Natural Gas Well #1

Science Photo Library

Miners Rally Against Coal Burning Limits #1

Science Photo Library