Downloading MarkEllis 1.1 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The application is categorized as Games. The actual developer of this free Mac application is Adriaan de Jongh & Rami Ismail.
From the developer:
MarkEllis is a game application in which you play the role of a train bridge inspector. You need to assess bridges on their structural integrity and see whether the train safely makes it to the other side. The game is based on the trivia that American train bridges are assessed by the companies that control the railroad.
You may want to check out more software for Mac, such as Jets'n'Guns, Rubicon X or Marathon Red, which might be related to MarkEllis.