different-landscapes:Natural History Museum, London, United Kingdom

different-landscapes:Natural History Museum, London, United Kingdom

nemfrog:  “Solar eclipse as seen from Lompoc, California, 1923,

nemfrog: “Solar eclipse as seen from Lompoc, California, 1923,

thebluechicory:  Natural History Flourite is Calcium flouride.

thebluechicory: Natural History Flourite is Calcium flouride.