The Tibia Minor was invented by Mr. John H. Compton, of Nottingham, England, one of the most artistic builders in that country. "The Tibia Minor bears some resemblance to Mr. Hope-Jones' Tibia Clausa, but being destined more for use on an open wind-chest, differs in some important respects. The stop is now generally made of wood, though several specimens have been made of metal. In all cases the upper lip is leathered. The tone of the Tibia Minor is extraordinarily effective. In the bass it is round and velvety * * * in the treble the tone becomes very clear and full * * * it forms a solo stop of remarkably fine effect, and in combination serves to add much clearness and fulness of tone to the treble, and, in general, exercises to the fullest extent the beneficial characteristics of the Tibia class of stop already detailed. If only by reason of the faculty so largely exercised, of thus mollifying and enriching the upper notes of other stops--which too often prove hard and strident in tone--the Tibia Minor deserves recognition as one of the most valuable of modern tonal inventions." [9] The Tibia Mollis, invented by Mr. Hope-Jones, is a Flute of soft tone, composed of rectangular wooden pipes. The name Tibia Mollis is also employed by Mr. John H. Compton to denote a more subdued variety of his Tibia Minor. Other Flutes found in organs are the Stopped Diapason, Clarabella, Clarinet Flute, Rohrfloete ("Reed-flute"), Wald Floete, Flauto Traverso, Suabe Flute, Clear Flute, Doppel Floete (with two mouths), Melodia, Orchestral Flute, etc., each of a different quality of tone and varying in intensity. The Philomela as made by Jardine is a melodia with two mouths. STRINGS. Under this head are grouped the stops which imitate the tones of such stringed instruments as the Viola, the Violoncello, the Double Bass, and more especially the old form of Violoncello, called the Viol di Gamba, which had six strings and was more nasal in tone. At the commencement of the period herein spoken of string-toned stops as we know them to-day scarcely existed. This family was practically represented by the Dulciana and by the old slow-speaking German Gamba. These Gambas were more like Diapasons than strings. Edmund Schulze made an advance and produced some Gambas and Violones which, though of robust and full-bodied type, were pleasant and musical in tone. They were at the time deemed capable of string-like effects.