Question

why did Helen appear in tits and bits

Answer 1

Well, this is a very tricky question. There is no mention of any reason

as to why Helen, the ghost appeared in sections. Though, Hallock asked her why

she materialized in sections, she gave no specific answer. 

The possible explanation to her appearing in sections could be this that

it could be the protocol to materialize or vanish. It was Helen's general style

of appearing and vanishing; whenever she appeared or vanished, she did it in

sections. You can say it was her style. 

Hope this helps you

Answer 2

Two reasons are there for Helen to show up in bits and pieces 
1. Helen believed that John was excessively occupied in considering a story. To get a handle on his consideration towards her she shows up in bits and pieces. 
2. Helen by ideals is really a ghost and perhaps she would have believed that on the off chance that she shows up in bits and pieces he may get dreaded and may stop the use of Ouija board. 
Henceforth Helen showed up in bits and pieces.

Hope its helps you

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