From Michael JG Meathook: Watson questions their use of guns.

I froze in the doorway, bags in hand as I stared at Holmes.

"What are you building?"

He did not even look up. "Nothing of import."

When I had left to run an errand, he had been pacing and thinking over his latest case, but now he sat at his desk, intently rigging something out of scrap pieces of wood, a tube, and rubber strings leftover from one of the factories. A small container of marbles sat on a nearby table.

Holmes despised doing anything simply to stay busy; whatever he built had some import, and I rarely found it a good thing when he refused to describe it. I said nothing, however, setting the reason for my errand on my desk before going up to my room to change clothes.

Holmes was still in the chair when I came back down, though the marbles were no longer on the table, and I wondered what he was planning as I made my way towards my chair. His most recent case was at one of the factories, I knew, but what that had to do with the handheld contraption he seemed to be building I had no idea. He had not shared the details of this case with me.

I was two steps from the door when he moved quickly, and a small, white object shot towards me. I reacted without consciously noting the projectile, and a marble hit the wall behind me with a resounding thump.

"Holmes!"

He glanced at me, lining his marble shooter up for another shot.

"Hold still, Watson. I need you to tell me how fast these are flying."

I barely dodged another marble. "Fast enough to bruise," I retorted. "I am not going to let you shoot me. What is that for?"

He lowered his weapon slightly, but I took another step away from him, adjusting to put part of a chair between us. I did not trust him not to keep trying.

"Well?" I asked when he remained quiet.

He huffed in frustration, finally relaxing his homemade gun from a ready position. "The Yard thinks my factory case is an accident, but there is a catwalk above where the man was found."

"What does a marble gun have to do with it?"

"The factory makes ball bearings," he replied, "among other things, and the man was found with several on the floor around him."

"You think someone shot him with a ball bearing?"

"It is possible, but I need to know whether the bearings would do the damage I saw. The factory uses these long rubber bands everywhere. I have already found that the more I use, the faster the marble flies, but I do not know if several bands would propel it fast enough."

"I can tell you right now that it is possible to send a marble flying hard enough to hurt someone badly."

"Not enough," he replied, shaking his head. "I need to know how many bands they used before I can set the trap. One would need at least five, I would think, depending on where the bearing hit, and this only has one. It should serve as a good baseline to prove or disprove my theory."

He aimed the gun again, and I put the door between us. "You are not shooting me with that thing. I don't care how many bands you have on it."

He sighed. "Fine. You shoot me, then."

He tossed the scrap gun across the room, and I stepped out from behind the door to catch it. He had used the tube as a handle, attaching the wood scraps along the sides to form a space between the opposite ends. A thick rubber band stretched across the space, with room to add several more around it.

"I rather doubt you want to be shot with this thing, either," I told him. This was not some child's pea shooter.

He waved me off, standing to give me a clear target. "I need to know what the bearings would do, and a marble is similar in size and weight."

I glanced between him and the small projectile. Harry had shot me with something similar when we were children, and the welts had hurt for days. Holmes did not know what he was asking.

"Hurry up, Watson. I need to take the results to the Yard soon."

I sighed. He was not going to like this, but I took aim at his thigh.

"Stop complaining, Holmes. I warned you it would hurt."

He grimaced, carefully inspecting the large, bruising welt on his leg with a gentle finger.

"You did not say it would cause such a welt," he grumbled. "Why did you hit me there?"

"Because marbles are heavy enough that aiming at your arm could have broken the bone," I told him. "Did your brother never hit you with a pea shooter?"

He shook his head. "If Mycroft ever considered such a thing, he outgrew it before I reached an age to be a target, and I never cared for such trifles. I found trouble in other ways."

I glanced up from my novel. "Like?"

He waved me off, and I huffed. Someday, I would get him to share some of those stories. Knowing him now, it was hard for me to imagine him as a mischievous boy.

He grimaced again and readjusted in his chair. "Did you have to hit me where I must feel it whenever I sit down?"

I smirked. "At the distance I stood, you would have felt it every time you moved no matter where I hit you. Hitting you there meant there was only soft tissue to bruise."

He huffed at me but made no reply. He captured the culprit a few days later, though I did notice the welt bothered him for nearly a week.

Maybe next time he would think twice about telling me to shoot him with something—especially after I so vehemently refused to let him shoot me.

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