Blue

“Can you show me something blue here?” I asked.

We were in the operating theatre again, and I was using the look-around-and-be-creative tool again.

“What about the nurses’ caps?”

“They are not really blue, and though you might call them light blue, that’s not the proper description either.” 

Actually, it was rather hard to find something blue. Properly blue, not light blue, or blue mixed with another colour. We did eventually find something, I forget what.

Blue, technically, is what you might think of as ‘dark blue’. What you would call light blue is really cyan.

“So, where would you see a cyan spot?” I asked. There were blanks looks all round.

“Ask the anaesthetist. He’s bound to have something, even if it’s Sudoku these days rather than the crossword.” And indeed, the anaesthetist was doing the Sudoku in the paper.

Newspapers are printed in colour these days, a process called CYMK, or cyan, yellow, magenta, black (or key). And somewhere you will find patches of CYMK, the printer’s controls.

This is a colour checker:

Blue is on the second row up, on the left; cyan is at the right end of the row.

Now, why do we have blues music, why are some jokes blue, and why do we sometimes feel blue — and when we are very blue, why are we then black? And if we think of blue as being cold and red as hot, why is it that the hotter things get that they go from reddish to blue?