52 BULLETIN OF THE BUSSEY INSTITUTION. 
new evidence upon this point, I have had the amounts of phosphoric 
acid and of potash very carefully estimated in a couple of samples of 
buckwheat straw, such as farmers have to do with. The samples 
were taken early in May, 1876, from barns on two separate farms at 
Wethersfield, Connecticut, by my friend Mr. Charles Wright, the well- 
known botanist. The straw had been threshed some time previously, 
in both cases. Sample No. II. was taken from a heap or mow of the 
straw that had been kept in the barn to be used for bedding cattle, and 
was in excellent condition. No. I., on the other hand, was a not par- 
ticularly good specimen, since in this instance the main body of the 
buckwheat straw had been thrown out from the barn at the time 
of threshing, and the sample had to be obtained by picking out special 
stalks, one by one, from a quantity of hay that had become somewhat 
mixed with the buckwheat straw after the threshing. This sample, like 
the other, consisted entirely of buckwheat straw, only the straw was 
not in such good condition in sample No. I. as in No. II. Both sam- 
ples had naturally been pretty thoroughly deprived of leaves during 
the process of threshing. The proportion of small branches and 
flower-stalks to the large stems or buts was rather smaller in No. I. 
than in No. Il. 
The phosphoric acid and the potash were not estimated in the ashes 
of the straw, but in the straw itself; that is to say, in solutions 
obtained by decomposing known weights of the straw with nitric acid, 
as has been explained on page 29 of this Bulletin. The purpose of 
this mode of treatment is to avoid the risk of losing any phosphoric 
acid or potash by way of volatilization in the process of burning the 
plant. Compare Volume I., page 199. 
The percentage of total ash was determined by burning some of the 
straw in a platinum dish in the usual way, and from the amount of ash 
thus obtained, and the amounts of phosphoric acid and potash found 
in the straw, the proportions of these substances in the ashes were 
calculated. 
The following results were obtained on analyzing the straws : — 
Mean of the 
Buckwheat Straw: — 1@ TT: two analyses. 
Moisture expelled at 110°. . . 10.35% 10.39%, 10.37% 
CGA BEN ee ea E AE 65: ce), gt OAD 5.86 6.21 
Ash, freefrom Cand CO,. . . 4.94 5.16 5.05 
Phosphoric acid in the straw . . 0.21 0.41 0.31 
Potash in the straw .-. .-.-. 1.72 2.50 2.11 
