The Curious Incident of the Dog in the Night-time 500 Words

These are the things Christopher told me that he remembers. There are 19 cows in the field, 15 of which are black and white and 4 of which are brown and white.
There is a village in the distance which has 31 visible houses and a church with a square tower and not a spire.
There are ridges in the field, which means that in medieval times it was what is called a ridge and furrow field and people who lived in the village would have a ridge each to do farming on.
There is an old plastic bag from Asda in the hedge, and a squashed Coca-Cola can with a snail on it, and a long piece of orange string.
The northeast corner of the field is highest and the southwest corner is lowest (He had a compass because his family were going on holiday and he wanted to know where Swindon was when they were in France) and the field is folded downward slightly along the line between these two corners so that the northwest and southeast corners are slightly lower than they would be if the field was an inclined plane.
Christopher can see three different types of grass and two colors of flowers in the grass. The cows are mostly facing uphill.
And there were 31 more things in this list of things Christopher noticed but I said that he  didn't need to write them all down. And I told him that it is very tiring if he is in a new place because he see all these things. Christopher remembers them so well that if someone asked him afterward what the cows looked like, he could ask which one, and he could do a drawing of them at home and say that a particular cow had patterns on it like this:
Then Christopher realize that he told a lie in Chapter 13 because he said “I cannot tell jokes,” because he does know 3 jokes that he can tell and he understands and one of them is about a cow, and I told him that he didn't have to go back and change what he wrote in Chapter 13 because it doesn't matter because it is not a lie, just a clarification. And this is the joke.There are three men on a train. One of them is an economist and one of them is a logician and one of them is a mathematician. And they have just crossed the border into Scotland (Christopher doesn't know why they are going to Scotland) and they see a brown cow standing in a field from the window of the train (and the cow is standing parallel to the train).
And the economist says, “Look, the cows in Scotland are brown.”
And the logician says, “No. There are cows in Scotland of which one at least is brown.”
And the mathematician says, “No. There is at least one cow in Scotland, of which one side
appears to be brown.”
And it is funny because economists are not real scientists, and because logicians think more
clearly, but mathematicians are best.