DEAR CLEAR-ORF, - I suppose you think you will solve the next mystery first. Well, you wont. Your brains want oiling a bit. They creak too much. Hugs and kisses from
THE FIVE FIND-OUTERS AND DOG.
The children giggled, especially at the last bit. You are an idiot, Fatty, said Pip. Its a good thing old Clear-Orf wont get the letter.
Oh, well send it all right, said Fatty, but as its written in invisible ink he wont be able to read it, poor mutt!
There was nothing to be seen on the sheet of notepaper. The orange-juice ink was certainly invisible!
But, Fatty, how can any one read invisible writing? said Daisy.
Easy, said Fatty. Ill show you how to read this kind. Got an electric iron anywhere?
Yes, said Pip. But I dont expect Mother would let us have it. She seems to think that anything she lends us is bound to get broken. Anyway, whatever do yo want an iron for?
Wait and see, said Fatty. Havent you got an ordinary flat-iron, Pip, if we cant borrow the electric one? There must be one in the kitchen.
There was. The cook said Pip might have it. If you break that, Id be surprised! she said, and Pip sped upstairs carrying the heavy old iron.
Heat it on the fire, said Fatty. So it was put on the fire, and well heated. When Fatty judged that it was warm enough, he took it off the fire, being careful to hold it with an iron-holder.
Now watch, he said, and in excitement they all watched. Fatty ran the iron lightly over the sheet on which he had written his invisible letter.
There it is! Its all coming up in faint brown letters! cried Bets, thrilled. Look! My dear Clear-Orf -
I suppose you will think... read Pip, in delight.
Yes, its visible now. Golly, thats clever, Fatty. I would never have thought that ordinary orange juice could be used as invisible ink!
Its better to know that than to know about the proper invisible ink, said Larry. Thats expensive,
but you only want an orange for this. Its marvellous, Fatty. Lets all write letters.
So they all took sheets of notepaper and wrote letters in orange-juice ink. They wrote rather cheeky letters to people they didnt like, and squealed with joy when the iron made the writing visible and they each read what the others had written.
Did you really mean to send old Clear-Orf a letter in invisible ink? asked Daisy, remembering what Fatty had said. But whats the point if he cant read it?
Just the fun of the thing, said Fatty. Hell be so wild to get a letter with no writing on it, and he wont know how to read it. We shant tell him either!
Fatty wrote out his first letter to Clear-Orf again, sealed up the apparently blank sheet of paper in an envelope and printed Clear-Orfs name on it.
Its rather a silly thing to do, I suppose, but itll puzzle old Clear-Orf, said Fatty, blotting the envelope. Well, now Ive taught you to write in invisible ink. Simple, isnt it?
Awfully, agreed Pip. But I dont quite see what use it will be to us, Fatty.
You never know, said Fatty. One of us might be captured in one mystery we solve, and we might want to get a message to the others. If we wrote it in invisible ink our enemies wouldnt be able to read the message.
Bets thought this sounded rather thrilling, though she didnt very much want to be captured. Then a thought struck her.
Well all have to carry an orange about with us, if ever we have enemies, she said. Wont we? Wed better not take very juicy ones, or theyll get squashed.
And wed have to take a pen, said Pip. Well, I shant bother till we have enemies.
I shall, said Fatty seriously. You never know when you might need to write an invisible message. I take tons of things about with me in my pockets, just in case I might need them.
This was quite true. The others were often amazed at the things Fatty carried about with him. As a rule he had practically anything needed in an emergency from a lemonade-bottle opener to a pocket-knife that contained twelve different kinds of tools.
My mother goes through my pockets each night and wont let me keep half what I want to, said Pip.
My mother never does things like that, said Fatty. She never bothers about my pockets.
The others thought that it wasnt only Fattys pockets his mother didnt bother about - it was Fatty himself! He seemed to come and go as he pleased, missed his meals if he didnt want them, went to bed what time he liked, and did more or less as he wanted to.
Fatty, you said youd show us how to get out of a locked room if the key wasnt on your side, said Bets, suddenly remembering. Theres time to do that, too. Will you?
All right, said Fatty. Take me up to one of your box-rooms, where I shall be out of the way. Lock me up, and leave me there. Come down here, and Ill join you in a few minutes.
Fibber, said Larry and Pip together. It really did sound quite impossible.
Well, try me and see, said Fatty. I dont usually say I can do things if I cant, do I?
In excitement the children took Fatty upstairs to a big boxroom, with bare boards inside it, and on the landing as well. They put him inside, then turned the key in the lock. Larry tried the door. Yes, it was well and truly locked.