Beety probably knows, Bill thought to himself. She's got ways the rest of us can't begin ta fathom.
Bill had nodded to a shape in the evening sky overhead, and shifted his stance, then made what sounded to humans like an insignificant animistic croak in the shape's dirction. The starling, flitting through the coal-smoke reek of the city streets,, realizing that it was being given a mission by a (more or less) eldritch being, darted off in the direction of the Tower.
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It was not long before the little male had relayed Bill's message to Mama Stella (Bill's mother), who passed it along to the rest of the flock in general, and Marley in particular.
"Artwork coming to life, is it?" Marley croaked to himself, shifting the trimmed wing a bit. He hated the way it felt, in the way that only a winged species can hate alteration to just one wing (the balance thus being thrown off, and said imbalance requiring adjustment and adaptation to regain the air).
OI!, Jimbo quorked, I knew it 'ad ta be bigger'n just us! Th' lion wedge on the Moat Gun said it 'eard the spell from outsoide th' Outer List, you 'member?"
Theodore, the Alpha Male of teh Tower ravens, opined, "I canna say I trust th' word've a cast-iron lion what gots a trough where 'is backbone oughter be, but yeah, that's a point, it is."
"What I don't understand is why I'd need to be there; it's not like I'm able to fly a straight line without flopping over upside down every third wingbeat."
It was something of a wonder to the ravens and the yeomen alike that Marley had figured out how to do that particular trick, but it was as odd to watch as it was uncomfortably vertiginous for Marley; it began to get difficult to tell where he was, whether up, down, or veering off one way or the other, after spinning around that way for more than a few hundred feet. He was improving at it, but he was dubious as to whether he could manage to get to the V&A by the prescribed time.
"Well, but there's nothing for it," Marley finally decided. "Bill want's me there, and he's seemed to have adopted me." Bonds of family, even family just recently gained by adoption, ran strong in Ravendom. "It's a chance to test out Ling Wa's Inner Needle Of Heaven, I suppose."
"Wing Ding's Noodle o' WHAT?!" Theodore exclaimed. "You Clock Knoights gets up ta some weird loowater, so ya do." He fumed a moment. "Alroight, ye gots me permission, call it a three-day pass, but you're ta come stright back 'ere at th' end of it, ya hear? I'll square it wi' th' Commandant roight after ye leaves." If a raven could smirk and crack a sardonic smile, Marley was sure old Theodore would be doing so just then.
So it was, that a Tower raven spun like a rifle ball up over the ramparts of the Tower to the bemuseent of the Wall Patrol, and into the night sky over London, headed in the general direction (in an odd, drunken kind of zig-zag*) of the Victoria and Albert Museum...
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*In other words, a "straight line" only in a manner of speaking.