More progress... but more things I need to calculate that I don't yet know how.

README.md

@@ -2,4 +2,38 @@
 
 Functions to compute relative humidity, absolute humidity, wet bulb 
 temperature, and other values related to humidity of air, given 
-partial data
+partial data.
+
+## General architecture
+
+### The packet
+
+The 'packet', in the terminology of this library, is a map which has bindings
+for some of the following keywords:
+
+1. `:actual-humidity`
+2. `:actual-vapour-pressure
+1. `:dew-point`
+2. `:pressure-pascals` 
+3. `:pressure-millibars` 
+4. `:saturation-pressure`
+5. `:relative-humidity`
+6. `:temperature`
+7. `:temperature-celsius` 
+8. `:temperature-kelvin` 
+
+These keywords represent variables in the pressure equations, and they are all
+to a degree inter-related; so if you have (or can assume) some of them, you can
+compute others.
+
+Rather than having a mess of functions all of which call one another, which 
+seemed likely to result in horrible messes and potential infinite recursion,
+there is one central function, `humidity.core/resolution`, which takes a 
+partial package and repeatedly tries to compute the values for more variables
+until it can compute no more, and then returns the enhanced packet.
+
+At present there are no checks to ensure that the packet makes sense.
+
+Associated with each variable there is a namespace which takes a packet, and,
+if that packet contains enough information to compute that variable, returns
+a numeric value, else `nil`.