[Lucy] turned on and found to her surprise a page with no pictures at all; but the first words were A Spell to make hidden things visible. She read it through to make sure of all the hard words and then said it out loud. And she knew at once that it was working because as she spoke the colors came into the capital letters at the top of the page and the pictures began appearing in the margins. It was like when you hold to the fire something written in Invisible Ink and the writing gradually shows up; only instead of the dingy color of lemon juice (which is the easiest Invisible Ink) this was all gold and blue and scarlet. . . And then she thought, “I suppose I’ve made everything visible, and not only the Thumpers. There might be lots of other invisible things hanging about a place like this. I’m not sure that I want to see them all.” At that moment she heard soft, heavy footfalls coming along the corridor behind her; and of course she remembered what she had been told about the Magician walking in his bare feet and making no more noise than a cat. It is always better to turn round than to have anything creeping up behind your back. Lucy did so.
Then her face lit up till, for a moment (but of course she didn’t know it), she looked almost as beautiful as that other Lucy in the picture, and she ran forward with a little cry of delight and with her arms stretched out. For what stood in the doorway was Aslan himself, the Lion, the highest of all High Kings. And he was solid and real and warm and he let her kiss him and bury herself in his shining mane. And from the low, earthquake-like sound that came from inside him, Lucy even dared to think that he was purring.
“Oh, Aslan,” said she, “it was kind of you to come.”
“I have been here all the time,” said he, “but you have just made me visible.”
“Aslan!” said Lucy almost a little reproachfully. “Don’t make fun of me. As if anything I could do would make you visible!”
“It did,” said Aslan. “Do you think I wouldn’t obey my own rules?”
From The Voyage of the Dawn Treader
Compiled in A Year with Aslan