diff --git a/ch07.asciidoc b/ch07.asciidoc
index 340c4c1a..650342d7 100644
--- a/ch07.asciidoc
+++ b/ch07.asciidoc
@@ -149,7 +149,7 @@ Merkle trees are used in bitcoin to summarize all the transactions in a block, p
 
 When N data elements are hashed and summarized in a Merkle Tree, you can check to see if any one data element is included in the tree with at most +2*log~2~(N)+ calculations, making this a very efficient data structure.  
 
-The merkle tree is constructed bottom-up. In the example below, we start with four transactions A, B, C and D, which form the _leaves_ of the Merkle Tree, shown in the diagram at the bottom. The transactions are not stored in the merkle tree, rather their data are hashed and the resulting hash is stored in each leaf node as H~A~, H~B~, H~C~ and H~D~:
+The merkle tree is constructed bottom-up. In the example below, we start with four transactions A, B, C and D, which form the _leaves_ of the Merkle Tree, shown in the diagram at the bottom. The transactions are not stored in the merkle tree, rather their data is hashed and the resulting hash is stored in each leaf node as H~A~, H~B~, H~C~ and H~D~:
 
 +H~A~ = SHA256(SHA256(Transaction A))+