Today I Learned

[DaveC426913]

It would also help if the traffic on the road were alive to the possibility of a mis-timed emerge instead of blasting along at 45 right next to a queue of stationary traffic and with an empty lane to his right...

Yes. I get very suspicious blasting along in a full lane next to a stopped lane.

Not just vehicles turning into traffic, but often simply vehicles in the stopped lane getting impatient and pulling out of the stopped lane.

My sister got zapped by this a while back. Totalled her car (she was fine). She acted like it wasn't her fault and that there was nothing she could have done. She was correct on the former but wrong on the latter.

 

[DaveE]

However, the problem is that the guy emerging can be stuck there forever if the queue in the left turn lane is replenished too quickly.

Or, he could turn right and go around to a better intersection to turn left from. Next time he can choose a better route. Then, he could write a letter to the powers that be to fix the traffic flow.

 

[Ibix]

Then, he could write a letter to the powers that be to fix the traffic flow.

...or just throw the letter in the bin, if the usual level of responsiveness of road planners on your side of the pond is the same as on ours...

 

[DaveE]

...or just throw the letter in the bin, if the usual level of responsiveness of road planners on your side of the pond is the same as on ours...

Yes, LOL. They already know.

 

[Bystander]

"Three 'rights make a left;'" you/he'll know better next time through the intersection.

 

[Ibix]

I generally agree. However, the problem is that the guy emerging can be stuck there forever if the queue in the left turn lane is replenished too quickly. So he may have to take an offered opportunity eventually. Of course, he should do so cautiously and creep-and-check out into the road - but because he wants to be nice to the guy who was nice to him he might skip that bit to emerge quicker, and that's when the trouble starts.

It would also help if the traffic on the road were alive to the possibility of a mis-timed emerge instead of blasting along at 45 right next to a queue of stationary traffic and with an empty lane to his right...

I got a couple of "skepticals" to this. In the UK, the example in the cartoon is, I think, covered by rule 173 of the Highway Code, which says to treat crossing the first carriageway and emerging onto the second one as the same as crossing one road and emerging onto a second. So there's nothing wrong with crossing to the gap in the central reservation (if your tail doesn't block the first carriageway) and then emerging on to the second carriageway just as you would emerge from a side road onto a main road with restricted view "upstream": carefully creep until you can see, giving plenty of time for vehicles on the main road to react. It would probably be better to wait for the queue to clear so you can see, but if that isn't happening any time soon it's not actually contrary to the rules of the road to go to the central reservation and emerge with care. At least, it's not contrary to the rules as written - you should certainly take the "assume the other guy's an idiot/assassin" advice in practice, and not only in this situation.

The same rule may not apply in your country (in fact, I'm pretty sure the rules are different in some places), so you may have different pressures.

And, of course, I am not a lawyer - I only play one on the internet.

 

[Flyboy]

And now, for something completely different…



… I wonder what that lava looked like. Would it appear any different than a more typical lava?

 

[Hornbein]

In Detroit the automobile companies had the leverage to dictate the layout of roads. As far as the main streets are concerned there are no left turns. To get the same effect, turn right. There is then a special U turn lane on your left.

At Taipei stoplights there is a special arrangement for the numerous motorbikes. No left turn. Turn right. At the head of the stopped waiting traffic there is a painted box reserved for motorbikes. Enter that, turn your bike around and you are ready to go straight. (Taipei is a very orderly place. It is dominated by the progeny of bureaucrats who fled the Communists. The defeated army escaped to the Golden Triangle where their descendants grow opium poppies. Violence-based order.)

 

[PeterDonis]

In Detroit the automobile companies had the leverage to dictate the layout of roads. As far as the main streets are concerned there are no left turns. To get the same effect, turn right. There is then a special U turn lane.

Yes, the famous "Michigan left". My experience when I lived in southeast Michigan was that it didn't really save any time, because you ended up waiting in the U turn lane for an opening at least as long as you would have waited to make an ordinary left turn.

 

[Hornbein]

Yes, the famous "Michigan left". My experience when I lived in southeast Michigan was that it didn't really save any time, because you ended up waiting in the U turn lane for an opening at least as long as you would have waited to make an ordinary left turn.

But while you wait you aren't blocking traffic.

 

[PeterDonis]

But while you wait you aren't blocking traffic.

Not on the original road you would have made a left on, no. But you might well end up blocking traffic on the other road when you find out that the U turn lane is backed up. I had that experience plenty of times.

 

[DaveE]

treat crossing the first carriageway and emerging onto the second one as the same as crossing one road and emerging onto a second.

Which leads to my pet peeve #2:
People that don't understand how to use the center turning lane, or why it's there if someone else wants to use it.

 

[Drakkith]

If you have the right of way, you have an obligation to use it.

My ex once decided to stay stopped when the stoplight turned green and instead waved on another car in an oncoming lane that was waiting to turn left across our path. Five to ten seconds of total confusion for everyone. Unbelievable...

 

[Tom.G]

Here in Southern California some (many, not all) drivers have begun to delay starting when a traffic light turns Green.

At first I thought this might have been a courtesy to the opposing traffic waiting to make a left turn.

Further reflection/experience highlighted a more likely reason:
They are waiting to avoid the cross-traffic drivers that try to 'Beat the Red Light' by speeding up... and barrelling through it!

 

[gmax137]

To get the same effect, turn right. There is then a special U turn lane on your left.

I saw this when I lived in New Orleans. I assimed it was a French thing.

Further reflection/experience highlighted a more likely reason:
They are waiting to avoid the cross-traffic drivers that try to 'Beat the Red Light' by speedin

Again, this too in New Orleans.

 

[PeterDonis]

They are waiting to avoid the cross-traffic drivers that try to 'Beat the Red Light' by speeding up... and barrelling through it!

On one occasion my wife would have been hit by a driver doing that if she hadn't followed the practice you describe.

 

[Hornbein]

I lived in Boston in 1974. Much disregard of traffic lights. They were taken as suggestions.

 

[BillTre]

Rumaging around LinkedIn I noticed that Veritasium has an ad for a writer/director.
Not something I expected to find.

 

[DaveC426913]

...there's nothing wrong with crossing to the gap in the central reservation (if your tail doesn't block the first carriageway) and then emerging on to the second carriageway just as you would emerge from a side road onto a main road with restricted view "upstream":

This was my take as well. In the diagram, there is room for the emerging vehicle to cross the frost half of the road. That is what I would do.

 

[jack action]

TIL that a lemon is a hybrid:

A genomic study of the lemon indicated it was a hybrid between bitter orange (sour orange) and citron.

And even the bitter orange is one:

It is probably a cross between the pomelo, Citrus maxima, and the mandarin orange, Citrus reticulata.

This means life never gave us lemons ... we made them. So making lemonade is a solution to a problem we created ourselves!

This just turned an optimistic proverb into a very pessimistic one.

 

[DrGreg]

Today I learned that the Mercator projection isn't what I thought it was.

When I was a child and teenager, I was told that the Mercator projection was what you got by putting a light source at the centre of a hollow transparent globe, and wrapped a piece of paper around the equator to form a cylinder. The pattern from the globe's surface projected onto the paper was the Mercator projection. That's what several pop-sci sources said, and (if my memory is correct) what teachers at school said, too.

Today I learned that was a lie. The projection described above is actually the central cylindrical projection. It's very similar to the Mercator projection near the equator but progressively differs as you move towards the poles. The true Mercator projection is a conformal mapping, which means that it preserves angles and, locally, the north-south and east-west scales are the same as each other. And that's why, historically, ship navigators liked it, because compass bearings at sea match angles on the map. (I say "historically" because I guess nowadays not many navigators use sextants and paper maps, but use GPS and computers instead.)

Lots of images comparing the two projections at: https://map-projections.net/compare.php?p1=central-cylindric&p2=mercator-84&w=1&sm=1&d=1

 

[Orodruin]

TIL that a lemon is a hybrid:

And even the bitter orange is one:


This means life never gave us lemons ... we made them. So making lemonade is a solution to a problem we created ourselves!

This just turned an optimistic proverb into a very pessimistic one.

TIL that the word citron, which is the Swedish word for lemon, exists in English but refers to what we in Swedish call a true lemon.

 

[berkeman]

TIL that the word citron, which is the Swedish word for lemon, exists in English but refers to what we in Swedish call a true lemon.

Wait, what?

https://www.gq-magazine.co.uk/cars/article/citroen-ds

 

[BillTre]

TIL that a lemon is a hybrid:

Since it seems that the hybridisicity of the lemon was determined by genome studies not historical breeding records, it may have been a natural hybrid (they do occur). Both the natural hybrid and one from a human breeding scheme would have similar genomes.
Maybe the citron is different.

 

[DrGreg]

TIL that the word citron ... refers to what we in Swedish call a true lemon.

https://www.gq-magazine.co.uk/cars/article/citroen-ds

I thought it was the Citroën 2CV that many said was a true lemon?

 

[Ibix]

I thought it was the Citroën 2CV that many said was a true lemon?

There was a guy who lived near where I grew up who had a 2CV with a spoiler on the back.

 

[BillTre]

 

[Hornbein]

Today I learned that the Mercator projection isn't what I thought it was.

When I was a child and teenager, I was told that the Mercator projection was what you got by putting a light source at the centre of a hollow transparent globe, and wrapped a piece of paper around the equator to form a cylinder. The pattern from the globe's surface projected onto the paper was the Mercator projection. That's what several pop-sci sources said, and (if my memory is correct) what teachers at school said, too.

Today I learned that was a lie. The projection described above is actually the central cylindrical projection. It's very similar to the Mercator projection near the equator but progressively differs as you move towards the poles. The true Mercator projection is a conformal mapping, which means that it preserves angles and, locally, the north-south and east-west scales are the same as each other. And that's why, historically, ship navigators liked it, because compass bearings at sea match angles on the map. (I say "historically" because I guess nowadays not many navigators use sextants and paper maps, but use GPS and computers instead.)

Lots of images comparing the two projections at: https://map-projections.net/compare.php?p1=central-cylindric&p2=mercator-84&w=1&sm=1&d=1

John Dee was in his days the most educated man in England. He went to Europe to catch up with the technology. Back to England he brought Euclid's Elements and the Mercator projection. This was crucial for navigation. John more or less founded the British Navy and the general concept of benevolent Empire.

It was widely believed that his mastery of witchcraft caused the sinking of the Spanish Armada. His home was sacked owing to his alleged diabolism.

I'm doing this from memory so don't entirely trust it.

 

[fresh_42]

TIL that Newton was forced into the home office due to a lockdown because of the plague.

Interesting perspective. And before you complain or oppose, this is exactly how the anthropological principle works: causality a posteriori.

 

[Hornbein]

Today I learned of the existence of the Westinghouse Five Million Volt Atom Smasher, a van der Graff generator in Pittsburg, PA. https://en.wikipedia.org/wiki/Westinghouse_Atom_Smasher#https://en.wikipedia.org/wiki/Westinghouse_Atom_Smasher#