You could also not. I worked on the "Ronson ship" found in the landfill (former landfall of Manhattan) in December of 1981 and at the time the underwater archaeologists tried to set a grid above the circa 1730s hulk and pull three tapes to measure points that were later calculated on a small handheld calculator. I've since worked on recording using infrared "total stations" (Lietz and Sokkisha which became Sokkia history) and that is a more accurate method. I've read here in the forum there are similar "beacon" systems using other parts of the electromagnetic spectrum.
Another method I've used on land/marsh is the close-range photogrammetry then in development by Rollei. Using a medium format camera and a few relative control points (1 meter rod) in the picture frame it is possible to resolve 3D measurements from photos registered with reseau marks on a digitizing tablet and software that calculates x,y,z from multiple photos. At the time around 1993 I heard Erv Garrison an archaeologist with the NOAA was testing it with a model in a swimming pool for its use in the description, for example, of documenting processes of site changes over time. This set of photos now with another at another time. A similar idea was in using the 35mm version of the documented camera and lens in the Metropolitan Cathedral in Mexico City. It would allow the investigation and measurement of changes in stone block movement after seismic changes I think.
The camera and software was being used by Prometric Technologies of Markham, Ontario and used in the architectural documenting and recording of "as-builts". Personally, I used it on the EPA Superfund Marathon Battery National Priority site in the Foundry Cove of the former West Point Foundry in Cold Spring, NY, where batteries for the Nike anti-missile system were made. I recorded plans and profiles with it in the recovery of either the prototype or of the return of the "Swamp Angel" gun platform found on wooden "grillage" in the marsh edge beneath the remains of the huge "Bridge Shop" which had burned down in the winter of 1912, a large metal working yard where magnetometer surveys, both terrestrial and over water were also part of the archaeological investigation. It was used in the incendiary bombardment of Charleston, SC in 1863, designed by the patentee of the R. P. Parrott "rifled cannon" which had a significant effect on the outcome of the US Civil War. We recovered two empty shells from the site where once President Lincoln had witnessed the firing of 200lb and possibly 300lb shells, across the Hudson River at the properties adjacent to the West Point Military Academy on the west shore.
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