Journal: August 19. Watchng the concrete dry.

George and Chris mixed up the concrete and poured it into the holes this morning.  They left a little after noon--as they'd just be sitting around waiting for it to set.

Realized I didn't know the difference between concrete and cement.  George explained that concrete is a mixture of sand, gravel, water and cement. Turns out most of us have long been confused on this subject.   Here's an official explanation bursting with details:

What is the difference between cement and concrete?
Although the terms cement and concrete often are used interchangeably, cement is actually an ingredient of concrete. Concrete is basically a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and portland cement. Concrete gets stronger as it gets older. Portland cement is not a brand name, but the generic term for the type of cement used in virtually all concrete, just as stainless is a type of steel and sterling a type of silver. Cement comprises from 10 to 15 percent of the concrete mix, by volume. Through a process called hydration, the cement and water harden and bind the aggregates into a rocklike mass. This hardening process continues for years meaning that concrete gets stronger as it gets older.
So, there is no such thing as a cement sidewalk, or a cement mixer; the proper terms are concrete sidewalk and concrete mixer.

Concrete Drying

Craig Seligman, the piano tuner came by to go fishing with his son Craig.  Told me that his entire shop burned down--fire caused by a mirror in shop reflecting sun starting blaze--many pianos up in smoke.

Waiting for concrete to dry, also waited for Carl the plumber to discuss possibilities for oil tank under porch. He arrived around four and agreed that the best thing would be to get a new oil tank and put it in the room downstairs with the well pump and pressure tank.  (The old oil tank is serviceable, but is under the porch--and if we build the porch properly, it will be buried and impossible to service it anything goes wrong.  One surprise after another, but so far nothing has been that difficult to solve.

The concrete dried just in time to get soaked by a completely unexpected rain (I hope it dried--I don't have a great eye for these things).  And in case any one is wondering.  I'd assumed the support posts would be inserted in the concrete--but that is not the case.  They just rest on it.