This is believed to be the oldest photo taken in the USA; Central High School in Philadelphia, by Joseph Saxton, 1839
The Wisconsinian Ice Age was an epoch when 2 massive Ice Sheets expanded over Canada. The Cordilleran Ice Sheet expanded over the western Canadian Rocky Mountains south of Alaska, while the Laurentide Glacier covered all of eastern Canada and even extended over New England, Ohio, and other midwestern states. (Ironically, most of Alaska stayed ice free during this time and consisted of a barren grassy environment known as the mammoth steppe.) About 30,000 years ago, the Cordilleran Ice Sheet and the Laurentide Ice Sheet conjoined into 1 massive glacial slab that blocked all human and animal migratory routes between Alaska and the rest of America. Formerly, scientists thought this barrier of ice existed from ~30,000 BP-~11,000 BP, but more recent studies suggest the 2 Ice Sheets began to separate as early as ~15,000 BP, creating an Ice Free Corridor that men and animals could have migrated through.
Map of North America…
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Having been on holiday and not quite back in the flow I decided that this object of the month could be an object from the present day.
It’s a trowel! We are all told when we start digging to get a solid cast WHS 4 inch pointing trowel, no bigger and definitely not a round-nosed builders’ gauge trowel, or a garden trowel!
Other pointing trowels are often too thin and can slice bone when digging, or they are too bendy and if not solid cast they can snap when digging up stones or attacking a hard sun-baked layer.
Over the years they shrink as the metal is worn away, and eventually the old favourite trowel has to be replaced with a new one as it is just too small for most work. You can tell whether the archaeologist who used a particular trowel was right or left-handed or even ambidextrous, which most of us are, due…
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