290 



SCIENCE. 



[Vol. II., No. 80. 



The prevalent theory of the action of mass is ex- 

 pressed, -jj- = kuv 



in which the diiiereutial 



expresses the rate of change in any substance, u and v 

 represent the masses taking part in tlie change, and k 

 is a constant. Some observations by Ostwald and 

 others indicate tliat some modifications of tliis theory 

 are needed. Determinations of tlie speed of reaction 

 require special care, both to measure lime in relation 

 to mass, and to control temperature and other condi- 

 tions. The chemical section of the Ohio mechanics' 

 institute has recently undertaken some work of the 

 sort, and invites co-operation. 



The following provisional system is suggested : for 

 volume, one cc. ; for mass, the chemical equivalent 

 expressed in mg. ; and for time, one hour. The 'unit 

 of speed would be the transformation of unit of 

 each active body per unit of volume and time. 

 Possibly the comparison of the constants of speed 

 or of chemical affinity with those of heat, elec- 

 tricity, etc., could be better made from the unit of 

 one second or 1,000 seconds. At least two observa- 

 tions of time and two of mass are required, and 

 preferably several, to determine the limits of error. 

 Determinations which do not accord with the hy- 

 pothesis that diminished s^jeed and diminished prod- 

 uct vary in the same ratio, need special investiga- 

 tion. In reciprocal reactions, some of the ratios 

 may be combined with constants of speed already 

 determined. By bringing all the facts into syste- 

 matic order, these data can be made of use for com- 

 parison in other physical-science fields. The paper 

 concludes with an extended bibliography of the sub- 

 ject, which will be very serviceable to workers in 

 this branch of research. 



Twelve months of lysimeter record at the Ne^w- 

 York agricultural experiment station. 



BY E. L. STUKTEVANT OF GENEVA, N.V. 



TuE lysimeters were described. They are boxes 

 of peculiar construction, containing selected samples 

 of soils in layers. The relative percolation of rain- 

 fall through these different soils, and the evaporation, 

 are determined by observations of the instnnnent. 

 The results are summarized as follows: Sod land 

 allowed 11.08 of the rainfall to percolate; soil of 

 which the surface was simply bared allowed 2.5. 8S per 

 cent percolation ; the cultivated soil passed 37.93 per 

 cent. The evaporation from the first of these was, 

 of course, 88.32 per cent; from the second, 74.12; from 

 the third, 62.07; the sum of percolation and evapora- 

 tion being held to account for the entire rain-fall. 



The composition of American -wheat and corn. 



BY CLIFFOED KICHAKDSON OF WASnlNGTOSf, B.C. 



This paper gave an account of results obtained by 

 the author in his work as first assistant chemist of 

 the U. S. department of agriculture. More than 200 

 analyses of wheat, and 100 of corn, have been made 

 during the last ten years under his supervision. It 

 appears that while our wheats are of somewhat lighter 

 weight, they contain less water, about the same ash, 

 more oil, less fibre, and less albumen, than the foreign 

 wheats. Among our wheats, only those from Colo- 

 rado, Dakota, and Minnesota equal the European in 

 albuminoids and in size of grain. The wheats of the 

 Atlantic states are poor in nitrogen. Corn, comiiared 

 with wheat, contains twice as much oil, less starch, 

 more water and fibre, and less of albuminoids. The 

 following table gives a condensed statement of the 

 wheat analyses : — 



Average percentage of nitrogen, albumen, etc., in wheats of the world. 



No. of 

 analyses 



Highest 



Weight 

 of 100 

 kernels. 



Highest 

 weight. 



Lowest 

 weight. 



Russia 



Russia 



North Germany . . . 

 South Germany . . . 



Germany 



Germany 



Sl'iiin 



Friince 



Scotland 



Australia 



Egypt 



Ail but Russia .... 



America 



America, except Colorado 

 Color.ido, 1881 .... 

 Colorado, 1882 .... 



Minnesota 



Michigan 



Missouri 



Oregon 



Atlantic States .... 

 Pennsylvania .... 

 North Carolina .... 

 Alabama 



3.12 

 2.34 

 2.24 

 2.17 



2.14 

 2.09 

 2.05 

 1.92 

 1.S3 

 1.46 

 1.79 



19.48 

 14.63 

 14.00 

 13.66 

 13.19 

 13.09 

 13.13 

 13.00 

 12.66 

 10.00 

 9.19 

 13.65 



12.00 

 11.62 

 13.40 

 13.06 

 12.79 

 12.00 

 11.44 

 9.17 

 11.18 

 11.25 

 10.46 

 11.32 



24.66 

 ]6.!i6 

 18.26 



17.16 

 16.63 

 15.94 

 14.88 

 17.15 

 14.47 

 12.44 

 10.63 

 14.00 



11.19 

 11.65 

 10.85 



3.532 

 4.833 

 4.209 

 3.364 

 4.116 

 S.502 

 4.800 

 3.057 

 3.211 

 3.782 

 3.137 



2.000 

 4.000 

 2.876 



3.275 

 4.250 



1.830 

 3.851 

 3.976 

 3 116 



Kuhn. 

 Wolff. 

 Von Bibra. 



Various. 

 Richardson. 



