BIENNIAL RF.rOKT, 1927 AND 1928 345 



Technical Bulletins 



11 Intensity or Rate of Laying in Relation to Fecundity. Hays, F. A 

 and Sanborn, Ruby. 16 p. November, 1927. 



One of a series of bulletins dealing with inherited traits in relation to fecundity 

 in the Rhode Is'and Red breed of domestic fowl. Intensity is an inherited trait 

 which vitally affects fecundity. In this study four measures of intensity have be^n 

 used : first sixty-day egpr record, mean size of winter clutch, net winter . rate of 

 laying, and annual rate of laying. From the standpoint of the breeder, mean size 

 of winter clutch is the most satisfactory criterion of intensity because it can be 

 accurately determined and because it is inherited. 



12 Net Correlations of Characters Concerned in Fecundity. Hays, F. A. 

 and Sanborn, Ruby. 9 p. December, 1927. 



This bulletin completes the series dealing with the five inherited traits concerned 

 with fecundity in the Rhode Island Red breed of domestic fowl. Net correlations 

 are presented, which more adequately portray the relative importance of the several 

 characters than do the simple correlations previously used. Annual egg production 

 is shown to be entirely independent of age at first egg ; to be dependent to an im- 

 portant and substantially equal degree upon length of winter pause, intensity ss 

 measured by winter clutch size, and degree of broodiness : but to be most intimately 

 affected by annual persistency. The multiple correlation of +.8(542 shows that the 

 five characters here considered largely control the annual egg yield. 



13 Washinji- Powders for Dairy Use. Pliillips, A. W., Mack, M. J., and 

 Frandsen, .L H. 10 p. May, 1928. 



1. Analyses of many washing powders on the market show four general classes, 

 containing eaifconate, caustic, phosphate and soap respectively. 



2. There is very slight variation in those powders which come in the same class. 



3. Laboratory and plant tests on these powders, on other mixtures, and on th(? 

 pure ingredients have demonstrated the specific roles played by each ingredient. 



4. A desirable composition for general dairy use has been indicated to be 60 per 

 cent sodium carbonate and 40 per cent tri-sodium phosphate. 



.1. By buying the commercial chemicals the price per pound of cleaner may be 

 reduced to close to 2 cents as compared with from 8 to 16 cents now paid for a 

 similar grade of product. 



6. The washing efficiency of the powders increased up to about 140° F. Below 

 9.5° F. the bactericidal action is greatly reduced. 



7. All powders showed disinfecting powers in 0.6 per cent solution, by renderin.g 

 the wash water sterile. 



14 Cutaneous Immunity in Relation to Contagious Epithelioma. Pyle. 

 Norman J. 16 p. June, 1928. 



A serological study of birds immune to bird pox, a study of cutaneous immunity 

 in relation to the disease, and the development of an efficient cutaneous vaccine for 

 the treatment of the disease are reported. 



15 The Extraction of Ajiple Juices in the Manufacture of Jelly. Fillers, 

 Carl R. 35 p. June, 1928. 



This investigation was an attempt to establish certain principles leading to greater 



economy in production, and providing a sounder basis for the housewife and com- 

 mercial preserver for the manufacture of a uniformly high quality product. In 

 general, two short (1.5-minute) successive extractions were desirable in order to 



obtain an optimum yield of juice containing sufficient pectin and acid to give satis- 

 factory yields of high quality jelly. When only one extraction of the fruit was 

 made there was a serious loss in jelly yield. Long extraction periods were unsatis- 

 factory because of destruction of the jellying power of the pectin. The best results 

 were obtained with a ratio of 1^2 or 1 part of fruit to each part of water added. 

 An extraction temperature of 212° F. was found most economical and effective. 



Red Astrachan. Red Siberian Crab, King David, Winesap and Mcintosh were among 

 the more suitable varieties for apple jelly manufacture. The development of a 

 method of tasting the consistency of jellies is described and the instrument pictured. 



