
N EW York AgricuLtuRAL ExprermeEnt Station. 491 
following acids: (1) acetic, (2) lactic, (8) sulphuric, (4) hydro- 
chloric. Below are given the results of the comparative trials: 
















Per cent. of 
Amount of Character of Character of 3 a 
KIND OF ACID USED. acid used. filtrate. precipitate. aecieineee 
PCOUIC BCIC 1. vucccins ec cth ss WS COC a OLOAT i eteis. ce eie's elese'e Flocculent...........- 0.395 
MUESGIG BCI) eco de auisisin ss 5.06 ONS CC val) VEN Yiieels sate «+ stein MIOCCUIENG o.com ne 0.074 
IC GIG ACIS Slava cars c's « crale'e s 0.75 cc. | Slightly cloudy...! Flocculent............ 0.396 
MSU LICACIO. .).fice es eaiseie's a5 Dee COU OIGAI eRe wel sila Flocculent....3....06- 0.394 
SGU CIC Nracicic viciest ices LIB SCC ea NU kyegiare’s cle. o's-niessie%s Flocculent............ 0.268 
INCRUIC CIC tiviiare cis efkis's 9,910 Oa CCR G LOA ciets la core, wales « Ploccule nts: sic x vices 0.465 
Sulphuric acid:....:...... O57 66.7) Cleats. 466 3-56 bi Somewhat gelatinous. 0.470 
Sulphuric acid............ R75 CO.) (VOIGAT Mia scles sa ceets Somewhat gelatinous 0.457 
Sulphuric acid...........- NEOs COs mmClOU Yan sc eas sis 6s Somewhat gelatinous. 0.417. 
Acetic acid . ic. .cscee eee 170m COssle CIOAMrccces yieies sce Flocculent............ 0.464 | 
Hydrochloric acid ........ Se OFS Com | Oloudy’. ists fans Gelatinous............ 0.410 
Hydrochloric acid ........ OFS RCCrr  ClOURYR > waace cc's .c Gelatinous............ 0.404 
Hydrochloric acid........ OUTS ICO yn PRUs fe vecte c.cere Gelatinous.........0.. 0.199 



Statement of results.— The results contained in the foregoing 
table show : 
First. That lactic acid gives results closely agreeing with those 
obtained by the use of acetic acid, when about one ce. of a ten 
per cent. solution of lactic acid is used, but if 0.5 cc. more or less 
than one cc. of lactic acid are used the results are very low. The 
precipitate was flocculent and filtered readily. 
Second. That a ten per cent. solution of sulphuric acid when 
used to the extent of 0.5 cc. for ten grams of milk gave results 
closely agreeing with those given by the use of acetic acid, but 
_ that when more than 0.5 cc. were used the results became lower. 
The filtrate was clear, but the casein did not separate in floccu- 
lent condition, having a tendency to become gelatinous. Several 
_  filtrations were required to get a clear filtrate, and filtration was 
slow. 
Third. That very unsatisfactory results were given by the use 
of hydrochloric acid, whatever the amount used. The filtrate 
was cloudy or milky, the precipitate gelatinous, the filtration 
extremely slow and the results low. 
Fourth. For the most satisfactory results, for the flocculent 
character of the precipitate, for rapidity of precipitation, filtra- 
tion, etc., the use of acetic acid had a great advantage over the 
other acids tried. 
(4.) Influence of temperature and time of digestion on pre- 
cipitation of casein.— In making the experiments, the results of 

