This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1861 edition. Excerpt: ...in the/coal measures, and might undoubtedly be made to afford a good mineral paint. A paint of this kind has been used for outside work at Lansing, and has stood well lor two years. GYPSUM. So much has already been said of the geographical and geological position of the gypsum of our State, that I only add a few memoranda. The following analyses were performed, at my request, by Prof. L. E. Fisk, of the Agricultural College: It thus appears that the sample of Grand Eapids gypsum analyzed, contained only 1.5957 parts in 100, of impurities, And the Ohio gypsum only 3.0572. Of these impurities, however, the sulphuric acid, potash and soda, are at least equally valuable with pure gypsum. These ingredients amount to.6816 in the Grand Rapids sample, and #1.1026 in the Ohio eample, leaving for the residual, worthless c mstituents of the former.9141 per cent, aad of the latter 1.9546 per cent. The following analysis is said to have been made by Dr. S. P. Duffield, of Detroit: Grand Rapids. Ohio, Water 19.00 20. 7O Lime 32.67 32.27 Sulphuric acid, 44.44 45.95 Organic matter and loss, 3.89 1.08 100.00 100.00 Here, on the contrary, the Ohio gypsum contains the most sulphuric acid. It appears, however, that the quantity stated for the Grand Rapids sample, is not sufficient to neutralize the lime by 2.23. By unfair selection of samples, such analyses may be made to show anything. The gypsum as it finds its way to the market is a mixture of different grades. The only true test would be an analysis of average samples taken direct from the market, not picked for the occasion. The samples sent Prof. Fisk were nearly the best of each. It is but justice to say, howover, that a large proportion of the Gi and Rapids gypsum, is ' equally fine with the...