iv Preface to the Eighth Edition.
been placed alongside of the older denominations in the formulae, as such multiplicity of figures often conduces to mistake; moreover, it is not practicable to secure synoptic parallelism between the incommensurable systems, unless by such compromises and allowances as are dangerous ; loose, inaccurate, and elastic rules of conversion repeatedly applied often completely transforming photographic instruc-tions. The metric system is a system standing by itself, the merits or demerits of which can only be fully esti-mated if the system is genuinely and primarily employed as a medium of thought and expression. Hence the incon-gruity of presenting our ounces, pounds, and drachms in an ill-fitting or inaccurate metric dress, is not conducive to a just estimate of the metric system. When metric formulae have appeared desirable as a means of elucidating the meaning of an authority, they have been given with-out alteration or any attempt to translate, adapt, or alter them; as, for example, on page 491.
THOMAS BOLAS. London, May, 1902.