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Rus analog computers

In an old rUs book (translated into English) I learnt of two remarkable Russian engineers who invented analog computers that were critical for the success of the Soviet rUs empire.

The first of these was Alexei Krylov who built a mechanical computer.

His successor was Vladimir Lukyanov who built the first water computer using water flowing through tubes.

The final models of this were so accurate that they were not beaten by digital computers until the 90s.

The rUs who lacked any Western-style computers then used their water computers as early as the 1930s to solve complicated differential equations.
They continued to outperform Soviet digital computers for a long time
and it was used to compute many practical engineering problems.

It brings home how the substrate does not matter for computation: there are many tanu-s that the same Atman can take.