A treatise on the theory and practice of obstetrics / By Wm. H. Byford.

  • William Heath Byford
Date:
1870
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the theory and practice of obstetrics / By Wm. H. Byford. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

    28/510 (page 14)
    diameter is reduced to less than three inches, we will not be able to feel the promontory with the index alone introduced. The ends of the fingers should he directed well upward, to get the right direction for the promontory. Unless the pelvis is very much contracted, the bilateral or oblique diameters cannot be measured by the hand. PELVIMETERS. Many forms of these instruments have from time to time been invented, but very few have been sufficiently simple and accurate to induce a general use of them. It would, I think, be consuming time and space needlessly to describe even a few of these forms. There are two pelvimeters of recent invention, either of which will give quite satisfactory results: one by M. Van Heuval, of P.russels, and the other is of my own construction. It is indeed a modification of Boudelocque's callipers. I prefer the last, because so much more simple in construction and application. I take the description of M. Van Ileuval's instrument from the last edition of Cazeau's Midwifery. As will be seen, it is a pair of callipers composed of two branches, one of which is fixed and the other movable. The first, A, B, is eleven inches in length, slightly curved, and flat- tened at its extremity; it is inserted into the vagina for internal measurement, and bears a hooked ring near its middle; beyond is a 1 i<m-graduated arc of a circle. It articulates below, like an ordi- nary pair of compasses, with the prolongation of a sheath in which Is inserted the lower extremity of the other branch. The curva- ture, Length, and hooked ring are the same as iu the Bmal] geome- tric ]>cl\ imeter. The second or external branch, C, B, may be lengthened at pleasure. It carries :it its upper extremity a Long horizontal screw, Eor the purpose of facilitating the disengagement of the COmpaSS after it.- internal application ; from thence it curves out- wardly, and finally, in descending, becomes straight and quadran- gular, and enters the above mentioned sheath. The Latter, which LB (pen at both ends, is furnished with a groove externally, for the purpose of receiving a projection of the branch, which pre- vents its escaping from the sheath. Its inner side is provided