pins on a 0 1 inch spacing for a total of 8 inches and arranged in a helical pattern the cylinder length k is 91 8 inches the dimension 1 is 11 8 inches the dimension m is 3 8 inch the dimension n is 1 2 inch the dimension p is 3 4 inch the dimension q is 1 8 inch and the dimension r is 1 4 inch in fig6 c the pins 402 have a diameter of 0 040 inch and the holes 404 have a diameter of 0 060 inch reconsidering fig4 in light of fig6 it may be noted that microdust laden air 218 230 is transported out of the internal parts of the main cylinder 212 and blocking sleeve 220 as described above and into a single pipe similarly the flow for the five counterflow separation slots of fig4 may be either individually transported into measurement apparatus such as electro optical sensors 44 64 illustrated in fig1 or may be combined into a single conduit 60 the individual flows q s for the five slots in fig4 are adjusted simply by providing variable restrictions in the flow lines as is well known in the art combining all of the dust plus trash thus released and separated by the mtm provides yet another meritorious use.