Line tension

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In the context of handwriting studies is under a line voltage , a script feature , understood that the fundamental component of the line quality is assigned. As a so-called “impression character”, the line tension is described in the rank of a binary nominal scale by attributes. Michel gives as examples:

  • 1. Can use “well-tensed handwriting”
    • Be "elastic, bouncy, supple or lively and flexible"
  • 2. Can “badly taut handwriting”
    • "On the one hand, limp, unsteady, not tense enough" or
    • “On the other hand, it is breaking, brittle, too tight”.

Summary

The “line tension” can be roughly described in handwriting as “good” or “bad”. The last-mentioned attribute can be used for "slack" or "rigid" font. These are valuable impression characters. A descriptive anamnesis of the characteristic of "line tension" is also possible through auxiliary ideas that make use of physical analogies . Purely static physical terms such as the mechanical tension or the elasticity of a structure are not sustainable or even misleading. Manuscripts as traces of writing generated sequentially over time can be written on piece by piece using vibrations . The above-mentioned categories can then be assigned depending on the ratio of the superposition component to the fundamental oscillation. Further attributes of the "line tension" can be e.g. B. can be found through the analogy of the lettering to mechanical waves in two-dimensional material structures. A “line tension” can only sensibly be assigned to sufficiently extensive movement elements in handwriting.

Origin of the term

Presumably, the term “line tension” was originally linked to the idea of ​​a certain tension and elasticity / plasticity of the muscular apparatus. This is also evident from Michel's analogy between writing and walking movements (see lit.), which can be seen as an attempt to include dynamic elements of the musculoskeletal system in the consideration. Although this association, which is historically rooted in graphology , is not scientifically founded and the terminology is hardly applicable from a physical point of view, the term “line tension” has become established and will continue to be used.

Auxiliary ideas for determining the line tension

The quality of the line tension can only be experienced and described by the handwriting expert through many comparative observations. The following analogies are suggested:

Mechanical tension, rope

When determining the character of the impression of the line tension, Michel refers to Heiß, who suggests the imagined transfer of the (mechanical) tension of a rope to the typeface as a “useful auxiliary idea”. Just like a rope, lettering can be “slack or taut”.

However, this auxiliary idea is only suitable to a limited extent, because the mechanical tension of a rope is to be understood as the force that acts on an imaginary cut surface through the rope. This also suggests an image that is too static, with the aid of which tremors, ataxias or other anomalies of the line shape can hardly be described. After all, a rope under the influence of gravity without any other forces - regardless of its tension - always describes a parabolic curve. At most, only very short lettering within movement elements is approximately curved in parabolic shape, and a statement about line tension usually loses its content in an “atomistic” approach. Rather, it has become common practice in specialist circles to apply the concept of line tension to more extensive movement elements.

In a microscopic order of magnitude - as opposed to "line tension" - another line quality takes effect, namely that of line security.

Elasticity / plasticity

The elasticity / plasticity as a physical analogy cannot help either, as this property of a three-dimensional, material object is used to describe its deformation under the influence of a force.

Vibrations

Handwritten traces of writing arise as sequential movements of a writing implement and can therefore be understood as a function of time. Since all physical vibrations can be described as more or less complex functions of time, it is advisable to look at at least sections of traces of writing based on images of vibrations.

Depending on the type and size of higher-frequency superpositions of the fundamental oscillation, one has:

Optimal line tension

  • Overlay components:
    • hardly present, pure fundamental oscillation
  • Approach of the lettering by:
    • approximately sinusoidal or parabolic arcs
  • Quality of the "line tension":
    • good, harmonious, springy, elastic, supple, lively and flexible

Suboptimal, slacker line tension

  • Overlay components:
    • moderately pronounced phase-locked harmonics
  • Approach of the lettering by:
    • flattened, meandering curves
  • Quality of the "line tension":
    • limp, unsteady, too little tense

Suboptimal tighter line tension

  • Overlay components:
    • strong phase-locked harmonics
  • Approach of the lettering by:
    • approximately rectangular, triangular or angularly connected lines
  • Quality of the "line tension":
    • high, very tense

Disturbed line tension

  • Overlay components:
    • pronounced higher-frequency, asynchronous superimposition components
  • Approach of the lettering by:
    • rough, irregular curve shape
  • Quality of the "line tension":
    • disturbed

Undefined line tension

  • Overlay components:
    • inconsistent, incomplete
  • Approach of the lettering by:
    • frequent interruptions, ataxias, unexpected changes in movement
  • Quality of the "line tension":
    • not defined

waves

Experience has shown, however, that very few movement elements in manuscripts can be represented solely by harmonic vibration functions, for example sinus functions or their approximations. Backward movements and line crossings in lettering must also be taken into account, which no longer have to be described by functions, but by relations.

A better auxiliary idea in this regard is obtained by adding spatial coordinates to the vibration, which can be described purely in terms of time, and thus changing from a vibration to a wave. Here, however, an essentially two-dimensional material structure may very well stand as an allegory for a lettering. Without claiming to be exhaustive, one could ask in this case, for example:

In which material structure is most likely to imagine that a wave runs through it that comes close to the lettering to be examined? Comes z. B. an elastic band or a hemp rope or an iron chain in question? The "line tension" would accordingly be elastic or evenly smooth or rough / angular.

Which forces act on this structure? Can the structure withstand the forces at all or do the forces only excite slight wave movements? Accordingly, one has a slightly wavy, expansive or overstretched stroke.

Is it possible to imagine a dampening of the waves in this structure? Does a wave fed in on one side run out becoming smaller or does it stay the same from beginning to end? In handwriting, this question corresponds to a "line tension" that is slackening over the length of the scriptural passage observed or that is continued tightly.

How does the wave come to a standstill in the said structure when the damping consists in the fact that it lies on a flat surface? Does it look loose, broken, splintered? The corresponding attributes can be transferred to the line quality.

Limits of the term

Only in rare cases should it be possible to determine the characteristic of “line tension” even in the case of essentially unconnected manuscripts. The question arises as to whether a definition of the “line tension” only makes sense in (internally connected) movement elements of current letters, or whether block letters or unconnected current letters can also show a “line tension”. The latter, however, is nonsensical, because how should a shaft run through a chain whose links are not connected to each other. At least in this case the chosen auxiliary concept fails. A “line tension” is difficult to describe in short movement elements, such as is predominantly found in unconnected current scripts or printed or block letters, in such a way that this characteristic could still be regarded as writer-specific and not as accidental.

literature

  • Lothar Michel : Judicial comparison of writings. An introduction to the basics, methods and practice . de Gruyter, 1982, especially p. 245
  • Rober Heiß and Inge Strauch: The Interpretation of Handwriting . 3rd, completely revised and expanded edition, Claassen, Hamburg