He pushed the paper into my hand. It was a letter.
“Go on,” said Bobbie. “Read it.”
So I did. It certainly was quite a letter. There was not much of it, but it was all to the point. This is what it said:
“MY DEAR BOBBIE,—I am going away. When you care enough about me
to remember to wish me many happy returns on my birthday, I will
come back. My address will be Box 341, London Morning News.”
I read it twice, then I said, “Well, why don’t you?”
“Why don’t I what?”
“Why don’t you wish her many happy returns? It doesn’t seem much to ask.”
“But she says on her birthday.”
“Well, when is her birthday?”
“Can’t you understand?” said Bobbie. “I’ve forgotten.”
“Forgotten!” I said.
“Yes,” said Bobbie. “Forgotten.”
“How do you mean, forgotten?” I said. “Forgotten whether it’s the twentieth or the twenty-first, or what? How near do you get to it?”
“I know it came somewhere between the first of January and the thirty-first of December. That’s how near I get to it.”
“Think.”
“Think? What’s the use of saying ‘Think’? Think I haven’t thought? I’ve been knocking sparks out of my brain ever since I opened that letter.”
“And you can’t remember?”
“No.”
I rang the bell and ordered restoratives.
“Well, Bobbie,” I said, “it’s a pretty hard case to spring on an untrained amateur like me. Suppose someone had come to Sherlock Holmes and said, ‘Mr. Holmes, here’s a case for you. When is my wife’s birthday?’ Wouldn’t that have given Sherlock a jolt? However, I know enough about the game to understand that a fellow can’t shoot off his deductive theories unless you start him with a clue, so rouse yourself out of that pop-eyed trance and come across with two or three. For instance, can’t you remember the last time she had a birthday? What sort of weather was it? That might fix the month.”
Bobbie shook his head.
“It was just ordinary weather, as near as I can recollect.”
“Warm?”
“Warmish.”
“Or cold?”
“Well, fairly cold, perhaps. I can’t remember.”
I ordered two more of the same. They seemed indicated in the Young Detective’s Manual. “You’re a great help, Bobbie,” I said. “An invaluable assistant. One of those indispensable adjuncts without which no home is complete.”
Bobbie seemed to be thinking.
“I’ve got it,” he said suddenly. “Look here. I gave her a present on her last birthday. All we have to do is to go to the shop, hunt up the date when it was bought, and the thing’s done.”
“Absolutely. What did you give her?”
He sagged.
“I can’t remember,” he said.
Getting ideas is like golf. Some days you’re right off, others it’s as easy as falling off a log. I don’t suppose dear old Bobbie had ever had two ideas in the same morning before in his life; but now he did it without an effort. He just loosed another dry Martini into the undergrowth, and before you could turn round it had flushed quite a brain-wave.
Do you know those little books called When were you Born? There’s one for each month. They tell you your character, your talents, your strong points, and your weak points at fourpence halfpenny a go. Bobbie’s idea was to buy the whole twelve, and go through them till we found out which month hit off Mary’s character. That would give us the month, and narrow it down a whole lot.
A pretty hot idea for a non-thinker like dear old Bobbie. We sallied out at once. He took half and I took half, and we settled down to work. As I say, it sounded good. But when we came to go into the thing, we saw that there was a flaw. There was plenty of information all right, but there wasn’t a single month that didn’t have something that exactly hit off Mary. For instance, in the December book it said, “December people are apt to keep their own secrets. They are extensive travellers.” Well, Mary had certainly kept her secret, and she had travelled quite extensively enough for Bobbie’s needs. Then, October people were “born with original ideas” and “loved moving.” You couldn’t have summed up Mary’s little jaunt more neatly. February people had “wonderful memories”—Mary’s speciality.