Another tangent about libraries…this time one that was in a government research laboratory a few miles from here. (I worked there for a while). Being the place it was (with a kind of academic feel about it), they were far too “gentlemanly” to impose actual fines, so you’d just get letters. I suppose in theory they could have got to you through your manager. However, one person we knew who worked there was a bit of a leading expert in his field, but notorious for not returning his books to the lab library. Apparently he’d had one out for at least 20 years or something like that. Probably because of his seniority, they would not have bothered to try to apply management pressure. There came the day when he left to go to another job (in a university as it happens), and there was the usual leaving presentation, and among the gifts was a new copy of this same book for him to keep… 
Did he blush and return the old one, or just brazenly accept the new and go? He may, of course, have forgotten that ‘his’ copy technically wasn’t his, in which case, if he politely didn’t say, “Oh, I have this already!” , no difference would have been noticed between that and brazenness!!
Once you’ve lived there, one never truly ‘leaves’ Aberystwyth.
Anyway, I’ve been reading a novel in Welsh and came across the phrase ‘lle chwech’. I can’t find it in my dictionary. In the story it’s a place, where someone climbs through the window to get to it? I translate it as ‘6th place’, what is it?
Tŷ bach! I don’t know whether in Welsh toilets they tended to have six cubicles - but it’s the place where you go to to ‘spend a penny’ 
I don’t know where I saw that first, but I have definitely seen it spelled out in those concrete letters produced by someone near Cardiff - was it on Heno or Bore Da on S4C?
Toilet… 
The place of six - from charming old workers outhouses with six holes in a row…!
It’s in my dictionary, listed under chwech.
So it is! To be honest I only looked it up in my pocket dictionary, which has more words in it, but less explanations. your dictionary is of course the best. However I know from watching Blackadder that a good dictionary should start with Aardvark, which your dictionary sadly lacks!
I know! I explained that to the publishers, but stupidly they didn’t agree and wouldn’t let me. Idiots.
Ardfarc?
What is the first the first word that could be found in the most obscure of dictionaries - the best I could find in GPC after “a” itself, would be Aaroniad - Aaronite, followed by ab (with and without a To bach).
Beth am Adfarch - Gelding or castrated horse.
Adfarchogaf - to ride again
(just posted two things consecutively and should have done them in the same post)
There was a story about the Aardvark on Tingatinga on S4C Cyw. I have now forgotten the word in Cymraeg used, I suppose I could see if its still available on line!
Google tells me it is grugarth -
Something like antbear I think, which is an alternative word for aardvark in English
Diolch. I had tried to re-watch on Clic and it had gone!!! None of my dictionaries seemed to have it!!
Oh, @garethrking you could now put it in yours!!!
I certainly could. 
A “hopefully” tiny question with an equally “hopefully” quick answer: I’m having difficulty figuring out when I should use “Do’n i” as opposed to “Wnes i” for the past tense. Are they interchangeable, so that it doesn’t matter if I use one and the challenge uses the other, or is there some grammatical nuance that I’m missing?
That one can be confusing at first. Basically “o’n i” (or “do’n i ddim”) is for something in the past that continued over time, like “I used to do (something)” or “I was doing (something) …” But “wnes i” is more for something that happened at a specific time, sort of like "yesterday, I did (something). To a certain extent they are interchangeable because there is a lot of grey area there, and you’ll be understood even if you get the “wrong” one, but that’s my understanding of the difference.
Seconding all Sionned said.
Though there very occasional differences in usage, it is equivalent to the difference in English between (using “to run” as an example) “I was running” on the one hand, and “I ran” /“I did run” on the other.
O’n i’n rhedeg - I was running
Rhedais i/nes i redeg - I ran /I did run.
The second has a “beginning, middle and end” aspect which the first doesn’t have, the first sort of stresses an “at the time aspect”.
Hope that helps!
I’ve seen farm, written as ffferm and ffarm - is it correct to use either?
Bore da pawb! Ma gen i cwestion…dwi’n Dwi’n ar gwers 23 course 3, fy cwestion ydy: pam defnydd “fedra’ i?” a ddim “ga i?” pan da chi’n siarad?
Any advice would be great!! Diolch