Читать книгу A Text-book of Paper-making - C. F. Cross - Страница 41

—It is advantageous in mounting transparent objects to employ a solution of the same refractive power as the substance itself. For this purpose, pure glycerin or a syrupy solution of calcium chloride may be employed; it is expedient to mix with either reagent a small proportion of acetic acid. The designation “neutral” has reference to the fact that these reagents are without sensible action on the fibres.