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One thousandth of a litre, equal to one cubic centimetre.

The 1864 solid units are the avoirdupois pound, avoirdupois ounce and grain; the liquid units are the Imperial measures. The grain is unchanged, while the old apothecaries' pound and ounce are not the units of the new formulary. ^[ref]

The relations for solids areTheir approximate French metric equivalents are:

For liquids,The approximate metric volumes are:

A millilitre is a cubic centimetre, and a litre is a cubic decimetre. These displayed equivalents are rounded; small differences from a period table's last digits reflect rounding and historical calibration conventions. A fluid ounce is a volume and an avoirdupois ounce is a mass. They cannot be interchanged for an arbitrary liquid without its density. Likewise, a drop is not a defined minim: its volume depends on the liquid and the dropper.

Volumetric analysis determines an amount of substance from the measured volume of a reagent of known strength that reacts with it in a known proportion. A measured aliquot is placed in a suitable vessel, the standard solution is delivered from a burette, and the volume required to reach the chosen titration endpoint is read. A pipette measures the aliquot; a volumetric flask prepares or dilutes the standard solution.

For a reaction $aA+bB⟶\text{products}$, if the concentration of the titrant $B$ is $c_B$ and the corrected volume delivered is $V_B$, thenWith volume in litres and concentration in moles per litre, the answer is an amount in moles. The corresponding mass is $m_A=M_A{n}_A$, using the appropriate molar mass. For an unknown solution of aliquot volume $V_A$,These are modern symbols for the same proportional reasoning that a nineteenth-century analyst could express with equivalent weights and a specified standard solution.

A suitable reaction is sufficiently rapid, complete and selective, with a recognisable endpoint. In an acid-base titration, an indicator can change colour near neutralization; other reactions use precipitation, redox or a colour intrinsic to a reagent. The observed titration endpoint must represent the required equivalence point closely enough. The reagent's nominal preparation alone is insufficient if its concentration changes in storage; standardisation of a solution, a reagent blank where needed, and correct reading of the meniscus control systematic error. A titration measures the intended analyte only insofar as interfering substances have been excluded or accounted for.