144 



The determination of fat rx creaih by the Babcock ^lETnoD 

 (pp. 5-11). — This is a comparison of fifty samples of cream of the per. 

 centages of fat indicated by the Babcock ceutrifngal method and by 

 tlie j-ravimetric metliod of tlie Liboratory. In all e\(H'i)t ten cases a 

 pipette made by A. L. Winton, jr., which delivered qnite accnrately <> 

 grams of cream, was used in measuring the cream for the Babcock test. 

 After measuring into the test bottles the cream Avas dihited with 

 12 c. c. of water, the test made as usnal, and the reading of fat in the 

 graduated tube multi])lied by 3. This pipette is said to do away with 

 the correction otherwise necessary in testing cream by this inethod. 

 In 2G cases the Baltcoek method gave higher resnlts and in 24 cases 

 lower results than the gravimetric method. The greatest ditterence was 

 0.5G per cent. The ditterence between the two methods was in 18 cases 

 a tenth of 1 per cent or less;, in 35 cases it was less than a quarter of 

 1 per cent; and in 7 eases it exceeded a third of 1 per cent. 



In coiisidprinfr tlit'so tij^iin-s and tlio accuracy of the method it nnist he home in 

 mind that the per cent of fat is from four to six times as great in cream as in milk, 

 and licnce a hirjfer dift'erence in the pcr<'enta<fe of fat found in cream hy the two 

 methods may not involve any larger jiroportifin of th<> total «|uanlify of hutter fat 

 than a much smaller ditfcrcnce in the ])er cent of fat found in milk hy ihi' two meth- 

 ods involves in the total ijiiantity <d" the fat of milk. 



The results ahove given lead us to helieve that tlie Hahcock method may lie made nf 

 very great value to cream-gathering creameries. It otfers to them a practical and 

 accurate method of ascertaining the actual <(uantity of Initter fat which each ])!itron 

 furnishes, so that payments may he hased not on vcdume of cream sujiplied, hut on 

 actual hutter fat, which is the raw material that the creamery manufactures. This 

 is ohviously the most satisfactory method of payment. For this purpose eaih 

 patron's cream should he weighed and sampled, and the fat in it determined hy tin 

 method descrihed. 



Tlie station proj>oses to study tlie juaetical woikiiig of tliis meiliod 

 at a ereaiiiery. 



Delaware Station. Bulletin No 13, July, 1891 (pp. 16). 



Leaf blight of the peak and the quince, F. 1^. Che.steb. 



]VI. S. (])lates 2, figs. 3). — This itielndes a deseii]»ti<»n of the etteets of 

 this disease on leaves and fruit, a brief a<'eonnt of the leal'bliglit fnn- 

 gus {EntomosporiKm nKiciihifiini). fornmlas for the fungicides used in 

 experiments by the antlior. and accounts of ex]ieiiments in sjiraying 

 diseased trees in four localities in Delaware. In the case of one of the 

 experiments, where five ai>i>licationswere made between IVIay 10 and 

 July 21, the following itercentages of sonnd frnit are re])orte<l for each 

 fungicide used: ^Modified can celeste S5.t, Bordeaux mixture S4.4. pre- 

 cipitated carbonate of co|)]»er 80. S, ammoniacal carbonate of eo]»iier 78..3, 

 carbonate of copper and carbonate of ammonia (i(>.3, no fnngici«le 42. 



So far as the effect of the several mixtures ujion the preservation of the f<diage i^ 

 concerned, there seemed to he no appreciahle difl'ereuce in their cHiciency. * 



The relative cost of the materials in these several fungicides was during th" 

 season of 1890 as follows, jter 1(>0 gallons: Carhonate of cojtjier and caihonate <>!' 



