Maths

How to Solve It by George Polya

Gödel’s Proof, by Ernest Nagel and James R Newman

The Maths of Life and Death, by Kit Yates

Physics

Gravity by George Gamow

The Strangest Man by Graham Farmelo

The Theoretical Minimum by Leonard Susskind

Why Does E=mc²? by Brian Cox and Jeff Forshaw

Biology and Medicine

Your Inner Fish by Neil Shubin

Sex, Power, Suicide by Nick Lane

Epigenetics Revolution By Nessa Carey

Chemistry

Excuse me sir, would you like to buy a kilo of isopropyl alcohol? by Max G. Gergel (my personal favourite on this list)

Ignition! An Informal History of Liquid Rocket Propellants by John Drury Clark

Engineering and Technology

Life 3.0 by Max Tegmark

How to Build a Car by Adrian Newey

The Code Book by Simon Singh