Letter | Published:

The Critical Velocity in Pipes

Nature volume 113, page 643 (03 May 1924) | Download Citation



IN the course of a recent conversation, Major A. R. Low pointed out to me that one state of steady fluid flow will not change to another unless there is a difference in the energies corresponding to the two types, or, as I prefer to put it, no change from one state to the other will occur spontaneously unless the change involves a dissipation of energy. If we call p/ the head in C.G.S. units, then in viscous flow the head lost in a length “x of a pipe can be written in the form

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Author information


  1. 26 Addiscombe Road, Croydon.

    • H. M. MARTIN


  1. Search for H. M. MARTIN in:

About this article

Publication history





By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.