volume in kettle

hey, i have been asking a lot of what may seem to be mundane questions to the more experienced lately, but i am getting close to doing my first all grain and want things to go relatively smoothly

so i was thinking today that when you start your boil, how do you know how much volume is in the kettle to begin with and when do you know when you've reached your target volume, if you do not have a sight glass

 

You use a gallon jug and a dowel or other stick. Fill up the kettle one gallon at a time and mark it on your stick. When you're brewing beer, just put the stick in the kettle and you'll know how much you have.

 

mash paddle / measuring stick combo sound cool??

 

After a few batches, you will get to the point where you can "eyeball" your pre and post boil volumes...basicly example would be to fill w/in an inch of the top and boil down to the handle rivets.