On Sun, 27 May 2018, 05:01 Tim, <xxxxxx@little-possums.net> wrote:
On Sat, May 26, 2018 at 08:48:06PM +0100, Timothy Collinson wrote:
> Is my calculation of a 40km horizon at height 200m on a size 5 world (let's
> say radius 2500 miles) about right? [1]

Yes, that looks fine for something like ocean or otherwise featureless
terrain.  If there are hills or mountains then they may block line of
sight to the theoretical horizon, or their upper parts may be visible
beyond it if the air is clear enough.

Yes, I have them looking out over the plains they just crossed on the train from Sadi.  At least, it's how I'm reading the world map of Pysadi.  I think the mountain range they crossed would be too far off to see.



> I needed to name some TL4 explosives (on Pysadi, harvesting howood)
> and came up with quadroglycerine - it was supposed to be a sort of
> homage to triticale being turned into quadrotriticale for Star
> Trek's Trouble With Tribbles episode.  But is the nature of
> glycerine such that that's just completely ridiculous?

It does seem rather implausible taken literally, but it wouldn't have
to literally mean glycerol with four nitrations.  Probably the closest
compound analogous to that would be erythritol tetranitrate (ETN),
which is an occasionally used explosive.

Erythritol is the 4-carbon extension of glycerol's 3-carbon form, and
perhaps it might be naturally produced by the native biology in a
larger role than on Earth.  Erythritol is produced biologically on
Earth by some fungi, so it seems quite plausible to posit wider
availability for it in an alien biosphere.  That could make it a
natural choice for nitration to form an explosive on a TL4 world.


Oooh, now funnily enough, I'd had them avoiding some fungi 'fronds', so that fits neatly.

It's not out of the question for someone to use quadroglycerine as a
common name or a trade name for ETN by analogy with widely familiar
nitroglycerine which has much the same chemical form.

Thanks for that.

I'm increasingly inclined to keep it as it is.  A local inaccuracy/affectation rather than my error!  I'm assuming that TL4 would imply that the general population (perhaps particularly under a religious dictatorship - even one as benign as that on Pysadi) would be relatively unacquainted with the chemical detail here.

I also liked the other suggestion of howoodite. Maybe I can work that in too.

In other news, I chatted with a doctor at church this morning and found out that what I'd invented for a PC death a couple of planets back, is actually quite reasonable.

I do love how Traveller takes me into knowledge areas that I'd otherwise be ignorant of.  Although I'm also aware that I could easily find out just enough to get myself into trouble with readers who know better.

But thanks again.

tc