I never got around to playing these games. The reviews were good so I bought 'em and hoped I'd have time. Ha! I guess you know I don't have the time. I've combined them to save money on shipping for you and me and allow me to offer them for less each than I've have to ask if shipped separately. 
They are 
Jack the Ripper by Adventure Company
Nikopol Secrets of the Immortals by White Birds/Got Game
Delaware St John Volume 3 The Seacliff Tragedy by Lighthouse Interactive
Secret Files Tunguska by Deep Silver- I believe they are also partly responsible for a line of my favorite games called "Gothic."