The thumb is a powerful finger because it is so different from the other fingers on the hand. For example:
- the thumb has two joints rather than the three joints that the other fingers have (I am counting the joint at the base of the finger as one of the joints).
- The thumb stands in opposition to the other fingers of the hand and moves in a direction that is counter to the other fingers. This counter-direction ability allows the thumb to form two kinds of grip: a power grip and a precision grip.
- The power grip is when the palm muscles squeeze to clamp down or hold something, like a hammer or other tool or a jar lid, and the thumb provides counter pressure.
- The precision grip is when the fingertips press against the thumb to provide a more "precise" grip, such as holding a writing utensil.
|Precision Bow Hold|
|Power Bow Hold (note the squeezed thumb)|
|Precision Violin Hold|
Both of these thumb uses are incorrect when playing the violin. I do not see so much of these uses and problems in piano teaching, where students generally attempt to play everything with flat fingers (like pressing levers), so I will focus the rest of this thumb discussion as to how it relates to string playing.
The purpose of the left thumb is to provide counter-weight. Notice that I did not use the word "pressure." I think of the left thumb as the balancing tool that tightrope walkers carry. The purpose of the balancing tool is to aide the balance of the tightrope walker. The purpose of the left thumb is to balance the feel of the left hand. It is not part of a gripping sensation. The left thumb merely rests softly and comfortably on the opposing side of the violin neck and provides a sense of balance to the hand.
|Hitchhiker "Banana" Thumb|
|No Smothering Moustache Man!|
|Inward Bent Thumb|
|Instrument Too Big? (note outward elbow)|
I recently encountered an older high school student at a summer camp who had a major left hand issue. This student attempted to play with only his fingertips. He held his left hand away from the violin neck, leaving a large hole between the base of his index finger and the side of the violin fingerboard. There was not much that I could do in this case, because the student had a teacher and the purpose of the camp was to learn the orchestra music. I observed though how difficult it was for the student to find the correct intonation when he played, because he was fingering "in the dark." In other words, he did not have all three reference points (thumb, base of index finger, and fingertip). Similar to the triangulation used to pinpoint someone's location, we have difficulty finding our pitch location on the fingerboard if we do not use all three of our reference points.
The right thumb serves a different purpose with the right hand than the left thumb does with the left hand. Instead of acting as a balance point for the other side of the hand, the right thumb serves to provide all of the support below the bow frog for the right hand above. How the thumb is placed against the bow stick will determine the type of weight that the hand and arm muscles provide and the direction that the weight will go.
As I wrote earlier, many students attempt to play with the fingertips. When we form the bow hold, these students attempt to grasp the bow stick with the first knuckles of the fingers, forming a grip similar to the precision grip we use to hold a pencil. These students are trying to control how the bow moves in a micro-management style, if you will. This kind of thumb use will result in a lighter tone and a wispy draw of the bow across the strings. The student may feel more secure when he uses the bow in this manner, but the type of sound produced will not reflect a good tone. These students tend to straighten out the thumb or allow little or no bend to it. Instead of using the tiptoe of the thumb, these students are using the backside of the thumb tip, like a precision grip between the finger pads.
Other students may understand the need for using the tiptoe of the thumb -- the uppermost tip end of the thumb -- but misunderstand how to place the thumb tip on the bow and at what angle. This placement is extremely important, because how the thumb is placed will determine which other muscles groups are in play, which in turn will affect the type of sound, volume, and tone that the student will produce with the bow movement.
|90 Degree Thumb|
Other students may deactivate the thumb and shift the hand weight to the pinkie or back side of the hand. This type of bow grip will prevent proper arm, hand, and finger movement. I have on occasion come across a student who allowed the bow hold to shift direction from index finger to pinkie finger as the student drew the bow across the strings, resembling the way that the balls of a Newton's Cradle pass the kinetic energy from one side to the other. This shifting right hand motion affected the student's finger motion and ability to used advanced bowing techniques.
The proper placement of the right thumb is at a 45 degree angle to the frog. The thumb should be bent at its first joint to allow for maximum flexibility and to provide strength to the weight created by the resting of the hand and arm on the bow stick. Notice that I used the word "resting." I am very careful to avoid words like "press" or "push down." Instead I use words like "rest," "sit," and "cradle." If my words imply any sort of action, I want my words to encourage action that releases or lets go of any action or activity. The arm weight is naturally heavy. There is no need to add to the force of gravity by pushing down on anything. Simply allowing the arm and hand to rest on the stick in a relaxed fashion will be enough to draw out the richest, fullest tone. But that's another article for another day. Today we focused on the thumb.