Silk Town-Thesmar Canal

gamarus wrote:

McGuiness wrote:So here's the Cliff Notes version. Siddarmark had already captured all of Silkiah and North Watch, and had Desnair trapped in Howard along a short, mountainous front, which it could have easily defended or even expanded well before Merlin showed up with innovations like rifles and artillery. However, some vicar with a lot of influence was probably rather upset that Siddarmark caused him to lose all the lovely bribes he wanted to skim from the Salthar Canal, and Desnair was pretty upset about losing them too. So they basically did a Hanth and got the CoGA to intervene, a couple of centuries after Siddarmark had seized the canal.

I'm sorry, but I can't see anywhere that Siddarmark had held Silkiah (or North Watch) for two centuries prior to the Treaty of Silk Town.
More likeliy, the latest spath of Siddarmark/Desnarian fighting rolled the Desnarians back once more, losing Silkiah and with Siddarmarkian forces in North Watch, the CoGA stepped in and dictated the terms in the Treaty.
After all, if Siddarmark had held Silkiah for centuries, don't you think they would have gotten much further into Howard each time the bloody minded Desnarian Emperors revealed their stupidity?

gamarus wrote:You cannot* use a single lock to get a barge up more than a few meters, maybe abit more than 5 meters. For that you need multiple locks in a chain, each gaining a few meters till you get to the level of the plateau. There will be a 'chain' of locks on each side of the plateau.

*There is some very dramatic barge elevators/escalators designed in the Victorian era to lift a barge out of a channel at one level and deposit it at another that exceed my number above by a wide margin. One is especially elegant, using counterveights and water taken on as ballast at the higher level it is operating enltirely without engines. That tough takes a lot of iron or steel, cables, gasquets and grease. And it's only practical if you need to scale a near vertical distance.


*quote="lyonheart"*Hi Isaac Newton,

Sorry, I don't think so.

The lock sets are 150-160 miles apart, so I don't think they are 'chains' in any way.

Actually, it is evidently a somewhat higher central plateau that Shan'wei's canal goes over, not around or through, which is very interesting for those who think it could have gone around the plateau or simple plowed through it as other canals did, but remember such problems didn't bother Shan-wei, who wasn't trying to impress the colonists with god like powers like the archangels.

Making a third of the canal fresh water, required quite a number of catch basins and aqueducts apparently, so they will need to be secured as well, but not as immediately as the the locks since I doubt they've been prepared for demolition the way the locks have.

I pointed out before that the fresh water will eventually be used for human and animal consumption when the canal goes all seawater some time in the future.

L

isaac_newton wrote:
Hi Lyon

I strongly suspect those two sets of locks are actually a pair of chains of locks, unless it is a really really low central plataeau! Was there anything more definite in the textev?

lyonheart wrote:Hi Gamarus,

Maybe not.

The Cascade Locks and Canal which I just clicked on were 90 feet high to deal with a 55 foot [17m] variation on the Columbia River, while the wiki Lock article reports that Portuguese locks on the Douro River have rises of 108 [33m] and 115 feet [35m], while the Irish have a couple of 100 feet [30.5m] locks on the Shannon.

Given another 300 years of improving technology in the Terran Federation, I suspect much higher rises are quite possible.

L

gamarus wrote:You cannot* use a single lock to get a barge up more than a few meters, maybe abit more than 5 meters. For that you need multiple locks in a chain, each gaining a few meters till you get to the level of the plateau. There will be a 'chain' of locks on each side of the plateau.

*There is some very dramatic barge elevators/escalators designed in the Victorian era to lift a barge out of a channel at one level and deposit it at another that exceed my number above by a wide margin. One is especially elegant, using counterveights and water taken on as ballast at the higher level it is operating enltirely without engines. That tough takes a lot of iron or steel, cables, gasquets and grease. And it's only practical if you need to scale a near vertical distance.

SNIP

isaac_newton wrote: quote="lyonheart" Hi Isaac Newton,

Sorry, I don't think so.

The lock sets are 150-160 miles apart, so I don't think they are 'chains' in any way.

Actually, it is evidently a somewhat higher central plateau that Shan'wei's canal goes over, not around or through, which is very interesting for those who think it could have gone around the plateau or simple plowed through it as other canals did, but remember such problems didn't bother Shan-wei, who wasn't trying to impress the colonists with god like powers like the archangels.

Making a third of the canal fresh water, required quite a number of catch basins and aqueducts apparently, so they will need to be secured as well, but not as immediately as the the locks since I doubt they've been prepared for demolition the way the locks have.

I pointed out before that the fresh water will eventually be used for human and animal consumption when the canal goes all seawater some time in the future.

L


quote="isaac_newton"

Hi Lyon

I strongly suspect those two sets of locks are actually a pair of chains of locks, unless it is a really really low central plataeau! Was there anything more definite in the textev? /quote /quote

Hi Lyon.

Let me explain why I think that there is likely to be a 'chain of locks'. We have a lot of canals in the UK with locks. Each lock chamber has a specific 'rise' [height difference between upper and lower sections of the water going into/out of that chamber].

That rise is not very large [I think about 20ft max, and more normally 10ft or so].

Therefore if you want to run a canal up an escarpment [edge of a plateau] which is several hundred foot, you physically must have a sequence [chain] of many locks running from top to bottom of the slope.

One famous one is the Caen Hill Locks [https://en.wikipedia.org/wiki/Caen_Hill_Locks] where 29 chambers give a total rise of over 200ft.

Hence my comment about the low central plateau. It just seemed unlikely to me that the central plateau was only 10-20ft above sea level.

[Edit] I see that in portugal there is a lock with a 100ft rise - but not sure if that purely under gravity.

lyonheart wrote:Hi Gamarus,

Maybe not.

The Cascade Locks and Canal which I just clicked on were 90 feet high to deal with a 55 foot [17m] variation on the Columbia River, while the wiki Lock article reports that Portuguese locks on the Douro River have rises of 108 [33m] and 115 feet [35m], while the Irish have a couple of 100 feet [30.5m] locks on the Shannon.

Given another 300 years of improving technology in the Terran Federation, I suspect much higher rises are quite possible.

L

SWM wrote:

lyonheart wrote:Hi Gamarus,

Maybe not.

The Cascade Locks and Canal which I just clicked on were 90 feet high to deal with a 55 foot [17m] variation on the Columbia River, while the wiki Lock article reports that Portuguese locks on the Douro River have rises of 108 [33m] and 115 feet [35m], while the Irish have a couple of 100 feet [30.5m] locks on the Shannon.

Given another 300 years of improving technology in the Terran Federation, I suspect much higher rises are quite possible.

L

The problem is not in the construction--the problem is filling and emptying the locks. Large rises require modern pumping. Safehold-tech locks can't be that high.

n7axw wrote:

SWM wrote: SNIP
The problem is not in the construction--the problem is filling and emptying the locks. Large rises require modern pumping. Safehold-tech locks can't be that high.

Do we have any idea how Safehold pumps are powered?

Don

SWM wrote:Windmills are mentioned in the text, so there are probably pumps powered by that. Otherwise, animal powered pumps.

isaac_newton wrote:

n7axw wrote:Do we have any idea how Safehold pumps are powered?

Don

Thanks SWM - thats sort of what I was thinking.

As to Safehold pumps - well, we know that steam power is out, so animal power I guess. I don't think I've heard mention of windmills in the text.