SB 3.11.8

laghūni vai samāmnātā
 daśa pañca ca nāḍikā
te dve muhūrtaḥ praharaḥ
 ṣaḍ yāmaḥ sapta vā nṛṇām
Word for word: 
laghūni — such laghus (each of two minutes); vai — exactly; samāmnātā — is called; daśa pañca — fifteen; ca — also; nāḍikā — a nāḍikā; te — of them; dve — two; muhūrtaḥ — a moment; praharaḥ — three hours; ṣaṭ — six; yāmaḥ — one fourth of a day or night; sapta — seven; — or; nṛṇām — of human calculation.
Translation: 
Fifteen laghus make one nāḍikā, which is also called a daṇḍa. Two daṇḍas make one muhūrta, and six or seven daṇḍas make one fourth of a day or night, according to human calculation.