In the early to mid-1950s, I served on recruiting duty in Wisconsin.  A Marine I recruited, by the name of Carlyle, went to to boot camp at the recruit depot in San Diego. Wanting to be the sharpest in his platoon, he used some brasso to polish his bayonet in preparation for an inspection there.

Now, anyone who has used brasso knows what it looks like when it dries up.  A sort of a whitish, powder.  He had left a little residue near the locking lug and failed to notice it when he fell out for the inspection.

As the DI and the Inspection Officer passed in front of him, the officer complimented him on how sharp he looked.  When the Inspecting Officer went around to the back of Carlyle's rank, the officer noticed the white spot on the bayonet.  The Officer yanked it out of the scabbard, and screamed, "Carlyle, do you see this?"  Carlyle answered, "Yes Sir!"  The Officer yelled, "And, just what do you think this is, Carlyle?" Caryle, without hesitation or even blinking an eye blurted out, "Bird Shit Sir!"

The DI hide his face to keep from bursting out laughing.  The entire platoon broke out into a roar of laughter, and the inspecting officer's face and neck turned beet red. He simply replaced the bayonet in the scabbard and never said another word.