It is believed that the Amsumati River is indicated three times in the English translation of 1898 (Mandala. VIII.96.13).
Translated by T. Ya. Elizarenkova. VIII. 96. (To Indra)
12. Prepare something that will please Indra, Praise with beautiful praise, strive to achieve with worship!
Try, O singer, not to shout!
Give a speech! Of course he will understand!
13. Drapsa climbed down to Anshumati, Krishna set out with ten thousand (warriors).
He, blowing with all his might, was helped by Indra.
The courageous thought dealt with the defeated (troops).
14. I saw Drapsa moving in different directions In the depths of the Anshumati river, Climbing down, black as a cloud.
I urge you, bulls: fight in the competition!
15. Then in the womb of Anshumati Drapsa, Shining brightly, he held (his) body.
With Brihaspati as his ally, Indra prevailed Advancing godless tribes.
In Sanskrit:
Amsa - shoulder, scapula, quadrilateral angle.
Amsala - healthy, strong, strong.
Mati - devotion, dedication, prayer, worship, hymn, praise, thought, design, plan, goal, intention, aspiration, concept, idea, decision, definition, establishment, inclination, desire, passion, measure, exact knowledge.
Translation of the name of the river Amshumati (Anshumati, aṃśumatī) - Plant-rich Soma.
It is assumed that Amshumati is another name for the Yamuna River, but no reason is given.
In the north, near the Ocean of Milk, the country of Patala is known - Talatala (Deep Valley), otherwise called Amshu (Amisha). It bordered the country from Ambara-tala. Talatala was located in the area of the Pai-Khoi mountains and the upper reaches of the Ussa River. On the Ussa River there is the Amshor River.
If there is an opinion that the name of the Amshumati River referred to the rivers of the Yamuna River basin, then most likely it is the Pronya River (the source of the Amshanka River and the Kerdy River). Pronya is the left tributary of the Oka. It flows through the territory of the Kaluga and Tula regions. Length 340 km. The Amshanka River flows in the Mikhailovsky district of the Ryazan region. Length 15 km. Left tributary of the Kerdy River (tributary of the Prony River). Length 60 km.
There are rivers: Amshanka - in the Kaluga region. A tributary of the Nepolod River (a tributary of the Bolva, a tributary of the Desna River). Omshanka is a river in Nizhnekamsk (Tataria).
Most likely, this is the Desna River (the source of the Amshanka River (a tributary of the Bolva River (Obolva, Abolva, Obolv), a tributary of the Dnieper, since Kuyava, mentioned in the epic, is located on it. The length of the river is 1130 km.
It is possible that both rivers, the Desna and the Pronya, were called Amshumati. The sources of the rivers are on the same hill, but they flow in different directions to the south and north. A similar situation exists in Ukraine, where two rivers named Bug flow from the same hill to the south and north.