I have found much trouble identifying the old word 'tis.
Does it mean "this is" or "it is?"
I have done some research and found that the dictionaries conflict.
One said 'tis :An old English word used in the place of this is ; a contraction of this is.
I showed this to my brother and he showed me another one it said 'tis :an old English contraction of the words it is.
'tis(this is) the voice of the lobster….or
'tis(it is) the voice of the lobster….