Staccato is one of the less important branches of bow technic.  There is a knack in doing it, and it is purely pyrotechnical. Staccato passages in quantity are only to be found in solos of the virtuoso type.  One never meets with extended staccato passages in Beethoven, Brahms, Bruch or Lalo.  And the Saint-Saens’s violin concerto, if I remember rightly, contains but a single staccato passage.

“Spiccato is a very different matter from staccato:  violinists as a rule use the middle of the bow for spiccato:  I use the upper third of the bow, and thus get most satisfactory results, in no matter what tempo.  This question as to what portion of the bow to use for spiccato each violinist must decide for himself, however, through experiment.  I have tried both ways and find that by the last mentioned use of the bow I secure quicker, cleaner results.  Students while practicing this bowing should take care that the wrist, and never the arm, be used.  Hubay has written some very excellent studies for this form of ‘springing bow.’

“The trill, when it rolls quickly and evenly, is a trill indeed!  I never had any difficulty in acquiring it, and can keep on trilling indefinitely without the slightest unevenness or slackening of speed.  Auer himself has assured me that I have a trill that runs on and on without a sign of fatigue or uncertainty.  The trill has to be practiced very slowly at first, later with increasing rapidity, and always with a firm pressure of the fingers.  It is a very beautiful embellishment, and one much used; one finds it in Beethoven, Mendelssohn, Brahms, etc.

“Double notes never seemed hard to me, but harmonics are not as easily acquired as some of the other violin effects.  I advise pressing down the first finger on the strings inordinately, especially in the higher positions, when playing artificial harmonics.  The higher the fingers ascend on the strings, the more firmly they should press them, otherwise the harmonics are apt to grow shrill and lose in clearness.  The majority of students have trouble with their harmonics, because they do not practice them in this way.  Of course the quality of the harmonics produced varies with the quality of the strings that produce them.  First class strings are an absolute necessity for the production of pure harmonics.  Yet in the case of the artist, he himself is held responsible, and not his strings.

“Octaves?  Occasionally, as in Auer’s transcript of Beethoven’s Dance of the Dervishes, or in the closing section of the Ernst Concerto, when they are used to obtain a certain weird effect, they sound well.  But ordinarily, if cleanly played, they sound like one-note successions.  In the examples mentioned, the so-called ‘fingered octaves,’ which are very difficult, are employed.  Ordinary octaves are not so troublesome.  After all, in octave playing we simply double the notes for the purpose of making them more powerful.