Block top - The block range and duration of your blockchain (in blocks) on creation of the present block Nonce - The transaction number for your from address (bear in mind this begins at 0 so a nonce of 100 would really be the 101st transaction submitted by this account) https://bookmarklinx.com/story20299001/a-review-of-blockchain-explorer-xrp-https-clancy-olesen-4-mdwrite-net-opening-the-record-your-resource-to-blockchain-investigation