Raised spot stitch
Make a vertical stitch across four threads of the canvas, then repeat the stitch through the same holes several times, until you can not get any more threads through.
Make a note of how many times you are wrapping around each stitch and keep this consistent throughout.
Move two canvas threads to the right and repeat to make the next stitch, making sure to match the number of times you wrap around each stitch.
Structure of stitch
Rachel Doyle, RSN Essential Stitch Guides: Canvaswork (2013) , p.80