For those who never saw any of the Burma Shave signs, here is a quick lesson in our history of the 1930's and '40's. 
Before there were interstates, when everyone drove the old 2 lane roads, Burma Shave signs would be posted all over the countryside in farmers' fields.

They were small red signs with white letters.  Five signs, about 100 feet apart, each containing 1 line of a 4 line couplet......and the obligatory 5th sign advertising Burma Shave, a popular shaving cream.

Here are more of the actual signs:

TRAINS DON'T WANDER
ALL OVER THE MAP
'CAUSE NOBODY SITS
IN THE ENGINEER'S LAP
Burma Shave

DON'T STICK YOUR ELBOW
OUT SO FAR
IT MAY GO HOME
IN ANOTHER CAR.
BURMA SHAVE

DROVE TOO LONG
DRIVER SNOOZING
WHAT HAPPENED NEXT
IS NOT AMUSING
Burma Shave

DON'T LOSE YOUR HEAD
TO GAIN A  MINUTE
YOU NEED YOUR HEAD
YOUR BRAINS ARE IN IT
Burma   Shave

SHE  KISSED THE HAIRBRUSH
BY MISTAKE
SHE THOUGHT IT WAS
HER HUSBAND JAKE
Burma Shave

 PASSING SCHOOL ZONE
TAKE IT  SLOW
LET OUR LITTLE
SHAVERS GROW
Burma Shave

CAR IN  DITCH
DRIVER IN TREE
THE MOON WAS FULL
AND SO WAS HE.
Burma   Shave

THE ONE WHO DRIVES
WHEN HE'S BEEN  DRINKING
DEPENDS ON YOU
TO DO HIS THINKING
Burma Shave

BOTH  HANDS ON THE WHEEL
EYES ON THE ROAD
THAT'S THE SKILLFUL
DRIVER'S  CODE
Burma Shave

AT INTERSECTIONS
LOOK EACH  WAY
A HARP SOUNDS NICE
BUT IT'S HARD TO PLAY
Burma Shave

A GUY WHO DRIVES
A CAR WIDE OPEN
IS NOT THINKIN'
HE'S JUST HOPIN'
Burma Shave

NO  MATTER THE PRICE
NO MATTER HOW NEW
THE BEST SAFETY DEVICE
IN THE CAR IS YOU
Burma Shave

AROUND THE CURVE
LICKETY-SPLIT
BEAUTIFUL CAR
WASN'T IT?
Burma Shave

THE MIDNIGHT RIDE
OF PAUL FOR BEER
LED TO A WARMER
HEMISPHERE
Burma Shave

SPEED WAS HIGH
WEATHER WAS NOT
TIRES WERE THIN
X MARKS THE  SPOT
Burma Shave

CAUTIOUS RIDER
TO HER  RECKLESS DEAR
LET'S HAVE LESS BULL
AND A LITTLE MORE STEER
Burma Shave

BROTHER SPEEDER
LET'S REHEARSE
ALL TOGETHER
GOOD MORNING, NURSE
Burma Shave