The first action of the Franco-Prussian War took place on 4 August 1870. This battle saw the unsupported division of General Douay of I Corps, with some attached cavalry, which was posted to watch the border, attacked in overwhelming but uncoordinated fashion by the German 3rd Army. During the day, elements of a Bavarian and two Prussian corps became engaged and were aided by Prussian artillery, which blasted holes in the defenses of the town. Douay held a very strong position initially, thanks to the accurate long-range fire of the Chassepots but his force was too thinly stretched to hold it. Douay was killed in the late morning when a caisson of the divisional mitrailleuse battery exploded near him; the encirclement of the town by the Prussians threatened the French avenue of retreat.
Who initially held a strong position during the battle at the border?
General Douay of I Corps

Unlike the American GPS, Russian GLONASS, and European Galileo systems, which use medium Earth orbit satellites, BeiDou-1 uses satellites in geostationary orbit. This means that the system does not require a large constellation of satellites, but it also limits the coverage to areas on Earth where the satellites are visible. The area that can be serviced is from longitude 70E to 140E and from latitude 5N to 55N. A frequency of the system is 2491.75 MHz.
What type of satellites does the American GPS system use?
medium Earth orbit satellites

Earthworms are Oligochaetes that support terrestrial food chains both as prey and in some regions are important in aeration and enriching of soil. The burrowing of marine polychaetes, which may constitute up to a third of all species in near-shore environments, encourages the development of ecosystems by enabling water and oxygen to penetrate the sea floor. In addition to improving soil fertility, annelids serve humans as food and as bait. Scientists observe annelids to monitor the quality of marine and fresh water. Although blood-letting is no longer in favor with doctors, some leech species are regarded as endangered species because they have been over-harvested for this purpose in the last few centuries. Ragworms' jaws are now being studied by engineers as they offer an exceptional combination of lightness and strength.
How do burrowing marine annelids help ocean ecosystems?
enabling water and oxygen to penetrate the sea floor