I don’t have any idea what the proper name for this pattern is but I have found some on line using the term Spaghetti Swirl. If anyone out there knows the right name, please feel free to contact me. They date to the 50’s or 60’s and the shape of the jug suggests Anchor Hocking or Hazel Atlas but there are no identifying marks on the glass. Very solid glasses with a rubberized coating for non slip grip.
Note: These have been SOLD
fabfindsblog 
My family had these in the 60s. We got a free one every week from the milkman when we ordered something above and beyond our usual order, like sour cream or cottage cheese. (We lived in southwestern Michigan.)
I do remember reading something about that recently. They are called Shat=-R-Proof glasses. Thanks very much for the info.