A lacuna is a gap or missing page in a manuscript; the term is also used to refer to gaps in musical compositions. Lacunae are extremely common in antique manuscripts which have been damaged by the passage of time, and they can be both frustrating and challenging to historians. Typically, a lacuna is clearly indicated in a transcription, usually with the symbol [...], as in the example of a sentence like: “The witness stated that she went to the [...] to purchase a [...] and a bag of potatoes.”
The most common reason for a gap in a manuscript is simply the passage of time. With older manuscripts, a lacuna can sometimes be reconstructed by using other copies of the manuscript or by using other contemporary information such as writings about that manuscript. In other instances, it may be impossible to figure out the phrase which once filled the gap, although historians often enjoy debating it anyway. A lacuna can also be deliberately created by someone who chose to obscure a section of text for various reasons.
In other instances, entire pages may be missing from a manuscript. These lacunae can be extremely unfortunate, since they sometimes indicate that the pages were removed deliberately, in which case they might have contained interesting information which could totally change the meaning and context of the manuscript. It is common for forged copies of missing pages to surface; in some cases, forged pages have endured for quite some time before someone finally proved that they were forgeries.
In modern manuscripts, a lacuna is relatively rare, since presumably the author is around to fill the gap. However, they do happen, especially in transcriptions of private correspondence or letters; biographers are sometimes frustrated by lacunae when they prepare material for publication. They also pop up in courtroom transcriptions, when a stenographer was unable to keep pace with testimony or when disruptions occur which made accurate transcription difficult.
The term has been used since 1663 to indicate a blank or missing piece of information, and in Latin it literally means “hole or pit.” The term comes from the Latin lacus, which means “lake or pond;” this root is also behind “lagoon.” Typically, the bracketed notation format is used in text when a lacuna is filled in, to indicate that the text is not original. In the example above, a printing with corrections of the lacunae might read: “The witness stated that she went to the [store] to purchase a [carton of milk] and a bag of potatoes.”