I cannot refrain from quoting Vardon again. He says on page 148:

There should be no sharp hit and no jerk in the swing, which should have the even gentle motion of a pendulum. In the backward swing, the length of which, as in all other strokes in golf, is regulated by the distance it is desired to make the ball travel, the head of the putter should be kept exactly in the line of the putt. Accuracy will be impossible if it is brought round at all. There should be a short follow-through after impact, varying, of course, according to the length of the putt. In the case of a long one, the club will go through much further, and then the arms would naturally be more extended.

This is wisdom as regards the put. There can be no doubt whatever about this being practical golf of the highest order, but Vardon rather spoils it by the following sentence in which he says, "In the follow-through the putter should be kept well down, the bottom edge scraping the edge of the grass for some inches."

Now, if that means anything at all, it means that although Vardon's conception of the put and its execution in many ways is excellent, yet he has been making for years the error which made James Braid a bad putter—in other words, he has been putting with drag. It is well known that for a very long time Vardon's weakness was his putting; and I firmly believe that the secret of his bad putting was this low follow-through with his put. I think that Vardon's follow-through in his put is now not so low as it was, and the consequence is that his putting has improved.

Vardon continues:

It is easy to understand how much more this course of procedure will tend towards the accuracy and delicacy of the stroke than the reverse method, in which the blade of the putter would be cocked up as soon as the ball had left it.

What is more natural, then, than that the blade of the putter should be cocked up immediately after the ball has left it? That is exactly what should happen in the perfectly played put. Vardon has already told us that the put is to be played with the "even gentle motion of a pendulum." Let us suppose for a moment that it was the weight of the pendulum turned side-wise which had struck the golf ball. It stands to reason that immediately the weight, which in this case answers to the face of the golf club, has struck the ball and sent it on its way to the hole, the face begins to "be cocked up."

Vardon here makes a totally erroneous claim. He claims greater delicacy and accuracy for the put played with drag as against that played as Braid now plays his puts. There can be no shadow of doubt that the put played with drag, or with a low follow-through "scraping the top of the grass for some inches," partakes much more of the nature of a tap than does the put which is played with top or a perfectly horizontal blow. If Vardon has not completely realised this, as I think he has, he will, ere long, do so, as James Braid already has done.

I need not here deal with complicated puts; that is to say, puts of such a nature that one has to traverse one, two, or more slopes on the way to the hole. These puts do not, in themselves, contain any of the fundamental principles of golf. Each one stands entirely by itself, and these are absolutely matters in which nothing but practice on the green can be of any use. It will be obvious to any schoolboy that if he has to run across five little hills on his way to the hole, and that three of these slant one way and two the other; and if we say for the sake of example that they are all practically equal in their width and slope, that it will be a case of four of them cancelling out on the good old plus and minus system of our schoolboy days, and we shall then be left practically to calculate how much we will have to allow for putting across the incline of one slope. This is not a case which I should think of giving myself. I merely give it because I came across such an illustration given in a book which is supposed to cater for those who desire the higher knowledge of golf, but as a matter of practical golf these situations but seldom occur.

Allowing for the drop in a green when one is putting across the slope, requires a lot of practice, and is most absolutely and emphatically not a thing that can be learned in an arm-chair, or in any golf school. It must be learned on the green itself.