THE TECHNICAL ANALYSIS OF C E n E N T S . BY S. F. Received 0;t
PECKHA3f
brr
L . 1901.
THErecent publication of the paper, by Mr. Bertram Blount. on "The *Analysis of Portland Cement,"l again brings to the attention of chemists this important question that had been allowed to slumber for some months. T h e very satisfactory results and conclusions reached by M r , Blount, with which I almost wholly agree, led m; to a reperusal of the papers read by Dr. Hillebratid, and to a reconsideration of the subject. T h e practical value of the conclusions reached by Mr. Blount cannot be overestimated, and I say this without any intention of underestimating the intrinsic value of d l the work done by Dr. Hillebrand,* and l f r . Richardson's committee. Whether o r no it is desirable to forniulate a process of analysis that all chemists may be expected to follow, the indirect results that have followed the work of this committee and the discussion that has proceeded from it, have proved to be of such value ns :o wholly justify all that has been done by all the parties concerned. I think, however: that i n the presentation up to this date, several very important aspects of the general subject have been lost sight of or overlooked. The discussion has proceeded as if there n-as little o r no variation in the quality of ceiiients. also as if there \vas one invariable purpose in the analysis of cements, and further. the analysis of the slitrr!. and other substances used i n the mbanufacture of cement has been mixed up with the analysis of cement. K S 01" TtIC c O M > I I S S I O N E K 5 0 1 ' . \ < L O I . S T ?
S E UT O K KSepteniher j o
iooi
[CONTRIBVTION F R O 3 1 THE V N l V E R S I T Y O F ~I,t,IiYOIS.%GRICULTCR.\L PERIMENT S T A T I O S
NO.
EX-
12.1
THE DETERnINATION O F ORGANIC CARBON IN SOILS. BY J. H . PETTIT A S D I. 0 . S C I I A C H . Received 5ei'tcrn:ier 16. 1 9 0 ~ .
I N COSSECTIOS
ivith the chemical side of the soil investigations now being carried on at this Station, it was desirable to know the organic carbon content of a large number of soils. The copper oxide combustion method was too long and tedious, and the wet combustion method, using potassium dichromate and concentrated sulphuric acid, did not give complete combustion on chemically pure organic componnds like sugar. Accordingly, Parr's' method for carbon in coal was tried for soils. -4fter some modifications this method gave results which compare very favorably with the copper oxide combustion method, and it has the ad.r-antape of being much inore rapid that; other methods used. 1
This Jour:ia:, 2 6 , ? a i
