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Comment Re:Bad system design? (Score 2) 88

There's plenty of other stuff in there making up the total system weight: structural framework, power supplies, and of course the mercury delay line memories, which were basically big sealed tanks of mercury. It also seems to have had magnetic drum storage, another heavy component. And I doubt weight of the system was a major concern anyway, as long as the floor could support it.

Comment Re:Why did these require so much power? (Score 2) 88

Perhaps because the low-power tubes were considered unsuitable for computing applications? Vacuum tubes in digital switching circuits have quite a different workload from those used in radios as amplifiers. The low-power tubes may not have provided fast switching performance, or they may have been unreliable in switching circuits. I'd think that power usage was a secondary concern for the designers of these computers; reducing it would be nice, but not at the cost of speed or reliability.

Comment Re:Help Me Out Here (Score 3, Interesting) 532

They're Iranian Air Force roundels: the outer ring is green instead of the blue used by the Royal Air Force. Although the Iranian Air Force's officer corps was purged after the Islamic revolution, its markings are only slightly modified from those of the old Imperial Iranian Air Force, which dates back to 1920, two decades before the occupation by the British during World War II. So it's not surprising that they were modeled after the British ones--or perhaps the French ones, since the French were actually the first to use the roundel. The French one is almost identical to the British, except that it has red on the outside and blue in the center. Anyway, the three-ring roundel is a very popular insignia for military aircraft, and lots of countries use it.

Comment Re:Up stairs and through walls (Score 2) 631

Most British (and American) Ships of the Line from the late 17th and 18th centuries had long range forward facing guns called "Long Nines". These were cast iron, "9 pound" guns usually 8 or 9 feet in length used as a "chase gun" firing from the bow or stern of the ship. On the larger ships such as the classic British "Man of War", often entire broadside batteries were "long nines".

Most warships in the age of sail used long guns as chase guns; they weren't unique to the British and Americans. And a long nine-pounder was only a modest-sized gun, like you might find on a frigate. The heart of the fleet, the ships of the line, would have 24-pounder or 32-pounder long guns for the broadside battery. (During the Napoleonic Wars at the end of the 18th century, short-barreled "carronades" became much more popular, replacing many of the smaller long guns.)

This was part of the reason why the British fleet ruled the seas for so long. They could take out an enemy from a range so far the enemy could not shoot back.

Actually, this is the exact opposite of the strategy preferred by the British. It's true that back in the days of the Spanish Armada in the late 16th century, they preferred to hit at a distance with longer-ranged guns, but this approach didn't work out as well as hoped; the guns' accuracy and energy fell off much too quickly with range. By the height of the age of sail in the late 18th century, British ships preferred to close to point-blank range (one reason why short-range carronades became so popular). The keys to their naval superiority were better seamanship (leading to more efficient and effective ship handling), aggressive tactics (take the fight to the enemy whenever you could), and better gunnery, which for the British meant that their gun crews could pump out more shots more accurately than their adversaries could. The British believed that in a close-range fight, their ships could be relied on to deal much more damage more quickly than their enemy, to the point that they could board or otherwise force the enemy to surrender, and that any damage their own ships suffered could be handled and patched by their well-trained crews. It was a belief often confirmed in practice.

In this style of fighting, the main role of chase guns was either to slow down a fleeing adversary enough to allow the British ship to close for a short-range battle, or if pursued by a clearly superior enemy, to slow him enough to allow you to escape.

The British kept to this approach until the development of accurate long-range rifled guns forced them to abandon it.

Comment Re:Found this joke about why QANTAS jets do not cr (Score 1) 374

Pilots: Number 3 engine missing.

Engineers: Engine found on right wing after brief search.

Heh, nice one, but alas that joke seems to be meaningless for modern airliners. It comes from the days of piston-engined airliners, because only piston engines "miss" (misfire in one or more cylinders).

Comment Re:I know Murdoch is crooked... (Score 1) 150

Robert Maxwell also decided peoples' pension funds were his to play with. He's now living in hiding, or fell off a boat, which ever you choose to believe.

Considering his body was found by a fishing boat on the same day he went missing, and that he would now be 88 if he were still alive, the "living in hiding" supposition seems rather far fetched. :)

Comment Re:Disappointing (Score 4, Insightful) 104

Actually, some very big bull elephants have reached up to around 12 tons. But that's a minor point, because you're comparing apples and oranges.

"Only" 9 tons...for a flesh-eating biped. Think about that for a bit. No other land-dwelling meat-eater has ever come close to the size of the largest predatory dinosaurs. And all those dinosaurs were bipeds.

Elephants are herbivores, and they are strictly quadrupeds with columnar legs. The dinosaur analog for elephants are the sauropods, the largest of which reached up to 10 times the weight of the biggest elephants.

Comment Re:Science is Awesome (Score 1) 135

Ha! Thank you for first pointing out that my reliance on Wiki was naive, and then also for doing the research to prove that the unsourced Wiki slander might be rightheaded after all.

Glad to be of help.

Me? I don't have an opinion on it. The guy's explanation for the bones sounds reasonable to me, because it jives with my understanding of octopuses as among the brightest species on the planet. Still, I don't normally put a hell of a lot of weight on what one scientist says.

The biggest problem with his claim isn't octopus intelligence, which is definitely quite remarkable. (Still, making self-portraits would still count as extraordinary behavior for any animal, since it implies a particular arsenal of especially complex mental capabilities, and remember this is back in the Triassic, over 200 million years ago, when basic vertebrate brains, and presumably cephalopod brains as well, were still being refined.)

One big problems is that he has taken a site widely accepted as one which has preserved animals that died of various causes and decided that it's actually a predator's killing ground. That's a bit like claiming that bodies in a cemetary are actually a serial killer's victims.

Second is that these victims aren't just any prehistoric sea reptiles--they're shonisaurs, the giants of the ichthyosaurs. These were approaching the size of sperm whales and were arguably among the biggest ocean vertebrates that ever lived before today's great whales evolved. He's imagining that there's some gigantic cephalopod hunting these things, when no cephalopod, living or fossil, has ever been found even approaching such a size. Giant squid are big, yeah, but nowhere near big enough to take on and eat a sperm whale.

Third, he has no clear evidence backing these extraordinary claims--no body parts of the supposed predator, no clear marks of predation on the bones, no candidate animals to fill the role, no real trace fossils, nothing except suppositions about patterns he sees in the bone arrangements. But humans are good at finding patterns even when they don't actually mean anything.

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