Diagnosis can result from collecting and processing data. A cat scan can be a valuable tool in assessing such data.

The Captain was under the weather. Not sure what was wrong I stayed below decks late into the morning. The Kid had gone to shore for supplies and to look over the over-the-counter remedies for whatever is ailing you.

It was a quiet and still day. Maybe some fresh air, now that it was almost noon, would help shake the discomfort I was experiencing. On deck I breathed in the salt air and stretched some using the port shrouds. My usual good powers of observation were dulled due to the "brain cloud" feeling that had gripped me. No boats motoring around. No dinghies rowing or puttering here and there, and yet there on deck, even after attempting to rub hallucination from my senses, sat a cat. I stared. It stared. Neither one of us moved, squinted, or blinked.

"How'd you get here?"

No response.

The cat was dry. Nobody nearby. We continued to stare at one another. I remembered the time when The Kid had read to me about cat body language. Sometime ago we had shared a ride with a cat. It accepted our food, water, and company and then when we arrived in Key West it had jumped ship and never returned to the boat. So, what's this kitty up to?

"Don't go anywhere." I meow-like whispered to our new guest. I went below and found the article The Kid had catalogued.

Back on deck I noticed our uninvited shipmate's ears were now upright and pointing forward. I looked for ears in the article. Stopped to read under tail because I noticed that the end of the cat's tail was twitching. I was sure that the tail was a good indicator of something. I started to pick up all kinds of signals and fumbled through the article not able to keep up with all the data the cat was sending to me.

"Stay." I spoke like I was addressing a Cocker Spaniel. Once again I went below to find a dish for water. Back on deck I placed the dish about half way between us. I tried to get closer, but its tail whipped back and forth and I took this as a negative response.

We sat and looked at one another; then it inched over to the dish and lapped up some water and then crouched by the dish. It seemed that this kitty has been around boats and sailors. It knew to be cautious, but it also knew not to be afraid. As we continued to try to figure one another out, The Kid came back.

"Who's your friend?"

"So, you don't know how he got here either."

"She."

The Kid is very observant. I just barely knew it was a cat. I said to The Kid that I had no idea how it got on board.

"Let's see what she's thinking." The Kid said.

As the cat twitched, wagged, squinted, pointed and otherwise gestured, The Kid read the scan to explain what was being discussed.

A few points below are how to read a cat scan:

Ears:

Upright and pointin' forward signals the cat is alert but relaxed and ready to join the crew. Sideways pointing is payin' attention to what's happenin' on deck but unsure with the Captain, so is not relaxed. Ears upright and pointing back is perturbed by what's goin' on onboard and may become pirate-like. Ears pointin' back and flat against the side of her head is fearful and submissive but prone to become mutinous.

Eyes:

Narrow, slit like pupils could mean the cat is angry with shipmates but self-assured. Eyelids half-closed or fluttering it could mean the cat is sleepy. Looking at you eyelids fluttering and drooping, it's an indication trust in your captaincy.

Tail:

Tucked – fearful for safety of the vessel, defensive and ready to protect.  Half-mast and moving slowly from side to side – indicates mild interest in ship's activity.  Vertical or straight up – indicates anticipation for action and/or welcoming you aboard ship.  Vertical but curved to one side – indicates playfulness.  Curved over the cat's back – indicates expectation/monitoring the crew and the Captain's decisions.  Held low with tip twitching – indicates a stalking, predatory stance with skull and cross-bones being raised.  Frantically switching in wide arcs – indicates heightened affect/aggression to do battle on the high seas.

There is more body language data you can gather by doing a cat scan. It is good to know some of these and others when a cat decides to join with you no matter the duration.

Cats on board can earn their way on passages and while at anchor. This one will stay for now. But it is not clear what message it is sending. It seems to run a cycle of mixed signals. This Captain is not fluent in cat as is The Kid, however it seems that this cat is doing its own scan of The Captain. It is reading me, my tone, my body language and is responding by trying to communicate through some comparative method of etymology that...

"He wants to eat." The Kid interrupted my wanderings of meaningless interpretations.

"What? We don't have any cat food."

"She'll settle for some of the fish we have, I'm sure."

I crumbled up some pieces from a fillet we had been saving for lunch. Happy to share.

"How are feeling?" The Kid asked.

"Uhm, uh, pretty good actually."

I guess the cat scan did me some good.

The Captain and The Kid