The ink monitor

We used to make the ink   before the class
Powder  stirred in  water  turned it black
On the desk  were double  lids of brass
Sliding  back revealed the well ,its lack 

After  sums we  learned to write in ink
A dip in pen, lined paper and a space
We copied joined up writing,learned to link
Taking care, for ink can’t be erased

We used also used our pencils  now and then
The better off bought Biros  up the road
I had to save to buy a fountain pen
I have it still  to  write  down poems and  odes

So common now we never give a thought
Is ink what every human should avoid?