“It is the first time that stratlingite is recognized in ancient mortars,” Lucrezia Ungaro, the Trajan Forum archaeological chief”
??????
My Roman history professor told me years ago that one of the secrets to the durability of the roads the Romans built was the inclusion of volcanic ash in the mortar used to hold the stones in the fossa in place.
Maybe it was still just a theory then (instead of a proven fact), though.
Beats me. Maybe “pozzolanic volcanic ash” is special.
Ever wonder at the scope of knowledge lost when the Library of Alexandria burned?
No...its been known for years.
I, too, heard about it.
Big difference is that they didn’t know WHY it worked but that it did work. And it was discovered through trial and error.
The admonition to use the crackly stuff is a give away.
As a general statement, I have noticed that we have collectively seemed to have forgotten all we once knew. This article has a gollygeewhiz tone that I find at once fascinating and repulsive in its ignorance.
Or I am missing something.
I have an old book on the Canals of NY. During the early construction, there was a lawsuit here regarding a patent on "cement" and I believe the comparison was specifically made to Roman Concrete.
Your professor was right, and it's been known for quite some time.
Volcanic ash and stone was used in the concrete used to make roman fish pens.
The ash's addition makes a "hydraulic" cement, capable of setting under water.
There was also a roman governor in ancient Israel that used the same hydraulic concrete to build massive docks and seawalls in a city called (IIRC) "Ceasaeria".. (sp?)
Romans also added wheat flour to their mortars and cements.
The gluten creates a glue that helped the mortar / cement to bond more firmly to the stones used to build walls.
http://en.wikipedia.org/wiki/Caesarea_Maritima
Scroll down to the chapter on the harbor.