[ A good question. Childermass has a few of his own that he's dwelling on, in part of why he's yet to appear. Something about Strange is off and, even though he's heard enough to make a few guesses as to why, whatever truly did happen in that black tower has been a mystery to him.

There's safety in being wary, but, at the very least, he's sure it really is Jonathan Strange. Who else would stop to complain at a bunch of mirrors when hopelessly lost? ]

The same magic that created it in the first place. [ Which isn't really an answer, but he's not about to bring up the Ringmaster just yet. Lord knows how fast this conversation would derail if he brought the word "fairy" into it. In any case, he's finally decided to step out, appearing in some previously difficult to see gap between two mirrors. As of yet, he's not so changed by the carnival that anything stands out as unusual, save for the silver color that's since replaced his usual eye color. ] It could be that they're not even connected to the King's Roads.

[ Because who wants magicians wandering in and out on a whim, right? ]