Tunnel boring machine

so many members are lacking of knowledge and they confused that "what ppt i will give" they are having zeal to give a ppt but lack of topics they didnt participate so that it is my way to give names of topics and help them to give ppts. giving ppt is a vey good habbit for every one to get knowledge and transform knowledge to others to get information regarding this topic you will visit the site given below

http://en.wikipedia.org/wiki/Tunnel_boring_machine