Proud anti-fascist & bird-person

  • 55 Posts
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Joined 1 year ago
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Cake day: June 12th, 2023

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  • From Hydraulics of Roman Aqueducts : Steep Chutes, Cascades and Dropshafts (PDF warning):

    The designs of dropshaft cascade, as well as steep chute followed by dissipation basin, show that the Roman aqueduct engineers were able to design specific features to cope with steep sections. It remains unclear whether they had some understanding of the hydraulic principles, or worked by observations and trial and error.

    Most aqueducts were enclosed (covered) along their entire length, limiting the possibility for gas transfer at the free surface. Thus, the downstream waters were low in dissolved oxygen content unless reoxygenation devices were installed. I suggest that dropshafts may have been introduced in place of steep chutes in order to reoxygenate the water as well as to dissipate the energy of the flow. Aeration technology is commonly used today to reoxygenate depleted waters and to enhance the water quality. I recommend that further work by archaeologists focus on the excavation and survey of chutes and dropshaft to confirm this hypothesis.















  • Don’t forget Mary Anning!

    Anning searched for fossils in the area’s Blue Lias and Charmouth Mudstone cliffs, particularly during the winter months when landslides exposed new fossils that had to be collected quickly before they were lost to the sea. Her discoveries included the first correctly identified ichthyosaur skeleton when she was twelve years old; the first two nearly complete plesiosaur skeletons; the first pterosaur skeleton located outside Germany; and fish fossils. Her observations played a key role in the discovery that coprolites, known as bezoar stones at the time, were fossilised faeces, and she also discovered that belemnite fossils contained fossilised ink sacs like those of modern cephalopods.

    Anning struggled financially for much of her life. As a woman, she was not eligible to join the Geological Society of London, and she did not always receive full credit for her scientific contributions. However, her friend, geologist Henry De la Beche, who painted Duria Antiquior, the first widely circulated pictorial representation of a scene from prehistoric life derived from fossil reconstructions, based it largely on fossils Anning had found and sold prints of it for her benefit.