On OS X, you access Windows shares (the "H:" drive) through SMB, not FTP. In Finder, select "Go > Connect to server..." from the menu. A small dialog will pop-up, where you can specify the URL for the server. The URL for a Windows server is:
smb://servername/sharename
... you can also specify your username and password for that share as part of the URL:
smb://username:password@servername/sharename
... though, if you don't, you'll be prompted for the username and password. In your case, the URL would look like this:
smb://server_4/folder
... and you will have mounted on your system a share named 'folder' which will appear on your desktop and/or the sidebar (depending on your preferences for showing connected machines and disks). Just like AFP shares, you can drag the icon into the login items panel for your user account and it will automatically connect when you login (and are on the network where the share is).