> Lm, So ONS Soi1Craparison senples of soil for determination of 87-90 c..°0 These will assist in evaivetion and ssleation .0 of analysise 7) -'.. Ul: 2 >. " Oo us Dre AlcuenJ.r of the Departmant of .., 0 preparing large _sveral nethods. .veilable methods Previous comparisons have been linited in scope, but have shown large deviations between methods, and one bread experiment is now. requireéds Intercomparison Report | A summary of all laboratory intercomparisons on all samples run to date has been completed, and will be issued as en NYO -eport. Agreement between laboratories is gensrally good, but there are enough major variations to warn against placing reliance on single results. Control Milk The Analytical Branch has been running an analysis monthly on large batches of dried milk. The first lot, run from June of 195) through April of 1955 showed values of O.91 4 Ooll ppe/g Ca for 10 analyses. The second lot, run from August of 1956 through Decenber.of 1956 showed values of hod 3 Oo7 pue/g Ca for 16 enalyses. Although there ars insufficient data for a complete statistical analysis, the results indicate some deviations greater than expected from counting errer. Future control samples will be ashed and blended before use to remove the variation between cans in " the seme lot.