Definition of "slopping"

[…] the birth of Christ, when these long valleys […] were still extensive lakes, sloppings of the great deluge, not yet dried up in time to pass away from the evaporation of the sun's rays and the labour of mankind.

1860, Horace Marryat, A residence in Jutland, the Danish Isles, and Copenhagen

It is only fair to say that they could have been removed by hand in the dark, but on examining the table, I was unable to see any of those sloppings of water which might be expected to follow such an operation.

1921, Arthur Conan Doyle, The Wanderings of a Spiritualist