Measuring (māṇa or tulanā) is the act of determining the size, length or amount of something.
A common unit for measuring volume was the nālī, the amount that could be held in a segment of bamboo (Ja.IV,67; Vin.I,249). Another common unit was the doṇa. Originally a doṇa was a wooden receptacle of standard size used for measuring out raw rice.
The bones of the average adult male after cremation weigh between 1 and 1.8 kilograms, which, in the case of the Buddha’s remains, could have easily fitted into a doṇa. Other units of measurement were the accharā, catubhāga, ammaṇa, kukku, paṭṭha and the vidatthi (Ja.III,318; VI,339; V,297; 385).
The Buddha said that we should not just show love (metta) towards others, but a particular type of love; a love that is immeasurable (appamāṇa). Some love is besmirched by jealousy, lust or the desire to control.
All these types of love can be measured because they are to some extent limited.