REPORT OP THE CHEMIST. 197 



Studies of fish transportation to prevent decay have been con- 

 tinued. Perhaps no other perishable food is shipped long distances 

 with so little knowledge of what is required to insure arrival in good 

 order. The work was begun in Florida and at the end of the ship- 

 ping season transferred to the Pacific coast, where transcontinental 

 hauls are under observation. A Yearbook article upon the fish 

 industry was published. Many analyses of food fish have been made 

 which show that the data now on record are inaccurate because as a 

 rule they were made without consideration of the season when the 

 fish were taken. The studies upon the chemical changes taking place 

 in fish in freezer storage begun last year have been continued. 



The investigation upon the improvement of the methods of canning 

 sardines has been brought to a successful conclusion. The industry 

 has very largely accepted the recommendations of the bureau. It 

 has taken steps to see that only sound fish are packed by imposing 

 upon itself an inspection service. 



Potatoes. — A process has been perfected for the drying of surplus 

 and cull potatoes with simple machinery for the purpose of utilizing 

 these tubers now largely wasted in certain localities in years of over- 

 production. The product can be fed to animals or be used as a size 

 or for the manufacture of gum, dextrin, or starch. Being dry, it can 

 be stored indefinitely and transported more cheaply than the potato 

 itself. 



A simple practical method of ensiling potatoes without cooking 

 or the use of pure cultures has been discovered. To the crushed raw 

 potatoes is added a starter consisting of 1.5 to 4 per cent of ordinary 

 corn meal. The loss from the resulting fermentation is negligible. 

 Cattle and hogs eat the product freely. Extensive feeding experi- 

 ments are planned for the coming year. 



Citrus and other fruits. — The development of a method for the 

 manufacture of citrate of lime from lemons has been completed, 

 while the development of a method for the manufacture of citric 

 acid free from contamination by heavy metals is well advanced. The 

 manufacture of lemon oil has been further studied and the determi- 

 nation of the seasonal variations of the oil and citric acid content of 

 lemons has been practically completed for certain sections of Cali- 

 fornia. A study of tangerines has shown that the green fruit has 

 value as a source of citric acid and that the oil has commercial possi- 

 bilities. The manufacture of marmalade stock has been undertaken. 

 A fine orange vinegar has been manufactured on a small commercial 

 scale which proaiises to find a market, though a limited one, because 

 it costs more to produce than the usual product. The determination 

 of the composition of California oranges with reference to season, 

 climate, soil, location, and methods of cultivation has been completed 

 and the results are being prepared for publication. The study of the 

 composition of oranges from selected trees has been of great assist- 

 ance to the Bureau of Plant Industry in studying bud variations for 

 the purpose of making selections in propagation experiments. Simi- 

 lar studies upon grape fruit have been begun with the Bureiu of 

 Plant Industry for the purpose of standardizing and improving the 

 varieties grown. A study to establish the range of variation in com- 

 position of mature Florida and California grapefruit has been under- 

 taken to be carried through several seasons. 



