The concept of gaps within a literary medium is certainly not a new one. In the 19th century writers such as Charles Dickens would write in installments leaving a "cliff-hanger" ending for the readers to respond to and provide suggestions as to a possible conclusion for the suspenseful, albeit fictional, event. Ironically, some of Dickens' works were published in a long novel after having been published in installments creating an altogether different effect.
The difference arises out of the cutting technique used in the serial story. It generally breaks off just at a point of suspense where one would like to know the outcome of a meeting, a situation, etc. The interruption and consequent prolongation of tension is the basic function of the cut. The result is that we try to imagine how the story will unfold, and in this way we heighten our own participation in the course of events. Dickens was a master of the technique; his readers became his "co-authors". -- (Iser, The Act of Reading, 191)
Although probably not as eager to write in installments and wait for reader's written responses to possible outcomes, proto-hypertextual authors such as Italo Calvino and Jorge Luis Borges utilized this technique of cutting in their works to encourage the reader's imagination to participate in the construction of the story. Calvino essentially describes his specific use of cutting in If On a Winter's Night a Traveler within the Diary of Silas Flannery,
I have the idea of writing a novel composed only of beginnings of novels. The protagonist could be a Reader who is continually interrupted. The Reader buys the new novel A by the author Z. But it is a defective copy, he can't go beyond the beginningÖ (Calvino, 198)
While Calvino never proceeds beyond the first chapter of ten different "books" to create a continuing narrative series of Iserian gaps, a hypertext can create the same sensations of absence, frustration and curiosity that actively invites the reader's imagination. The differences being that in a Hypertext the continuation of the story may or may not be located within the universe of the hypertext or, to appropriate the word of Theodore Nelson, the "docuverse"; that access to the continuation of a story may only be a linked word away.