Along about 1910 to 1920 the golf professionals were altering the body motions and
improving the golf club.One of the first big changes was in the grip. A great player
at this time, Harry Vardon,became well known due to this change. He is credited with
starting the overlapping grip now called(the Vardon grip).
The Vardon Grip:Both hands on the club firmly with the creases(the V's that the thumb
and the forefinger create)parallel and pointing over the right shoulder. The right palm
covering the left thumb and the little finger of the right hand overlapping the forefinger
of the left hand. This type of grip helps keep the grip correctly firm throughout the entire
swing. The left arm was extended more on the backswing with a deeper wrist cock instead of
loose at the top. They used a slightly open stance with the ball played more forward in
the stance, and the weight staying slightly more to center with the right knee straight.
At the top they keep the left knee straighten more than it is today at impact. This
created a hitting action against a firm left side motion.
To help this type of action the clubs were shortened and lightened which encouraged a
shorter and steeper plane swing( more upright arc). Bobby Jones had a tremendous impact
on the evolution of the golf swing. The results he got from his swing started the pros
studying some of the characteristics of that motion. Some of the more important changes
were the increased resistance of the legs on the backswing with firmer body moements;
and the ball being played closer and more to the left foot.
Many things influenced the evolution of the golf swing. Just to name a few; the type of
clothing worn, improvement of materials in the construction of golf equipment and golf
course maintenance. As late as the 1920's, golfers dressed to play the game of golf.
Knickers(plus fours), dress coat(no such thing as a sport coat), white shirt, long sleeves,
and of course a tie. For example, one of the great older golf pros from Scotland I
studied under back in Ohio would never dress in anything other than a white shirt
and tie until his death.
By contrast,today's golfers dress in light-weight clothing which allows more
freedom of motion.Clothing had a big influence in the evolution of the golf
swing; as well as the equipment - from a one-piece to a two-piece with hickory
shafts,then onto steel shafts; the first golf ball, the "feathery"(a leather
cover stuffed with feathers), to the "gutta perca"(a cheap form of
rubber)to the rubber wound with balata cover; the golf course maintenance
equipment from the horse-drawn to the tractor; and chemicals which improved the
grass and weed control, all shared in this evolution. The evolution of the
golf swing goes hand-in-hand with the eveolution of the golf club and balls
as well as the golf course.From the " feathery"to the 'gutta percha", from the
sheperds' crook to the hickory shaft with wood or steel heads was a giant step
in the evolution of the golf swing. 
