By the by, Boom, the fact that the insignia were black on an olive drab background means that they were 35 years old or less . . . prior to the summer of 1970, military insignia of that type (private soldiers' strips, and officers' insignia) were gold or silver in color. This is still true for dress uniform, but the black insignia are used on "battle dress."
single stripe [<]--private (called in the army, a private "E2")
stripe w/"rocker" [<)]--private first class
two stripes (no longer used)[<<]--corporal
three stripes (no longer used)[<<<]--sergeant
three stripes w/rocker [<<<)]--staff sergeant
three stripes w/2 rockers [<<<))]--sergeant first class
three stripes w/3 rockers [<<<)))]--master sergeant
Three stripes with three rockers, and a diamond between the stripes and the rockers is a First Sergeant; a star between the stripes and rockers is Sergeant Major; a star wreathed in oak leaves is a Command Sergeant Major--the highest enlisted rank.
A single gold bar--second lieutenant (navy=ensign)
A single silver bar--first lieutenant (navy=lieutenant junior grade)
Two silver bars ("railroad tracks")--captain (navy=lieutenant)
Gold oak leaf--major (navy=lieutenant commander)
Silver oak leaf--lieutenant colonel (navy=commander)
Eagle, the one you have--colonel (navy=captain)
One star--brigadier, the symbol on a map for a brigade (navy=commodore, not used now)
Two stars--major general, symbol on a map for a division (navy=rear admiral)
Three stars--lieutenant general, symbol on a map for a corps (navy=vice admiral)
Four stars--General, symbol on a map for an army (navy=Admiral)
Five stars arranged in a "circle," describing a pentagon in the center--General of the Armies, and there have been very few in history, in the navy that's Admiral of the Navies (?--beats hell out of me, i just don't know)
In the Confederate armies, one collar stripe=second lieutenant
two collar stripes=first lieutenant
three collar stripes=captain
a single start (five points)=major
two stars (five points)=lieutenant colonel
three stars, sometimes three five-point stars, sometimes one each of five points on either side of a six-point star=colonel
the same wreathed in oak leaves=any general officer
Those insignia were based on "old army" insignia before the Mexican War. A single insignia for general officers basically is saying that the exact rank is nobody else's business but another general, all you need to know is that he's a general. In a great many photos of the civil war, Lee is shown wearing the rank insignia of a colonel, rather than a "full" general, which is the rank he held in the old army before the war. He also scrupulously referred to his fellow southerners by their rank, but referred to Federal officers by their rank in the old army before the war, as at Chancellorsville, when he said: "I'm just sending General McLaws (Major General Lafayette McLaws) over to pay a call on Major Sedgwick (Major General John Sedgwick)." The war unhinged Mr. Lee somewhat.
This is a photograph of Lee in what was then a brand-new uniform, and he is wearing the rank insignia of a colonel, the highest rank he attained in the old army . . .
Learn all this, and you can really make a monkey of your brother.