i see what you are doing check your machine it may have an applique stitch on it there are two or three applique stitches you can use if not the one u used is close enough go to u tube and see the Eleanor Buns method of applique. i will try to explain. place you kaleidoscope face down on muslin or very light fabric some people use the dryer sheets after there wash sew almost all the way around it leave a place open so u can turn it right side out and the edge is Finnish then u can sew it to your block. does that make sense to you? i hope i wasn't too long winded hope that helps' your project is nice.
mema