74 



7 HE ALUMNI JOURNAL, 



only a few of them, the precipitates of these 

 bodies being retained in solution while hot ; 

 consequently they do not interfere with the al- 

 bumin reaction. 



The tube to which the acetic acid has been 

 added is best held between the tubes containing 

 the other reagents, any change in reaction being 

 more easily perceptible. The acetic acid is used 

 n addition to the reagents to detect soluble and 

 dissolved mucin, combined acids of oleoresius, 

 combined fatty acids, and other bodies yielding 

 precipitates in acid media. The albumin re- 

 agents all being used in acid media, form precip- 

 itates when such substances are present ; thus 

 the acetic acid prevents any errors which may 

 otherwise arise. 



If albumin be present there will be an increas- 

 ed cloudiness or precipitate in the tubes to which 

 the Millard's and Tanret's tests have been 

 added. When very faint traces are present 

 the opalescence produced, being distributed 

 throughout the liquid, is more easily perceptible 

 than the results obtained by applying the zone 

 or contact test ; the reagents being free from 

 color, and the urine also deprived of consider 

 able coloring matter by filtration through the 

 French chalk, gives greater delicacy to the re- 

 action. 



When the specimen is acid and the reaction 

 by Millard's test is more decided than that by 

 Tanret's and acetic acid, being least by Tan- 

 ret's, it shows the presence of mucin from bile 

 and the nucleo-albumin from bile. This mucin 

 appears to be the only soluble form of mucin 

 found in acid urine, and with and with it is al- 

 ways to be found the nucleo albumin, the mucin 

 from the mucous membrane being soluble only 

 in alkaline urine. The reason that Millard's 

 test gives this increased reaction is that it is a 

 more delicate reagent for mucin than either 

 acetic acid or Tanret's test. 



When the reaction is more decided in the 

 tube containing the acetic acid than it is in the 

 tubes to which the Tanret's and Millard's tests 

 been added, and no foreign bodies are precipit- 

 able by acetic acid, it shows the presence of 

 serum or para-globulin. 



When albumin serum alone is present, the re- 

 action is indicated in the tubes contanining the 

 Millard's and Tanret's tests, acetic acid giving 

 no reaction unless mucin be present, as in alka- 

 line urine or in specimens which have been 

 treated with alkali for clarification, when the 

 source is the mucous membrane, or in acid 

 specimens when it is derived from the bile. 

 When mucin is present in solution from either 



source the Millard's test always gives more in- 

 creased reaction than the Tanret's test or acetic 

 acid, being much more decided in the tubes 

 containing the acetic acid and the Millard's test 

 When any of the other forms of albumin are 

 present with the serum albumin, the specimen 

 is best treated with one-fourth its volume of 

 glacial acetic acid, heated to boiling, set aside 

 for one hour, then filtered through French 

 chalk as above directed. This separates mucin 

 from bile and mucous membrane, serum-glo- 

 bulin, and foreign substances, there being 

 retained in solution serum-albumin and the 

 nucleo albumin from bile, and these may 

 readily be differentiated by adding ferrocyanide 

 of potassa to the acetic acid solution, without 

 applying heat ; the ferrocyanide being a more 

 delicate reagent for the nucleo-albumin than 

 either Tanret's or Millard's tests, yields a 

 heavier reaction. 



Sugar. 

 Water, i drachm ; copper solution, 10 drops ; 

 alkaline tartrate, 10 drops ; heat to boiling, con- 

 tinue to heat for one minute ; if no change has 

 taken place it shows the solution to be reliable. 

 Add now 10 drops of the urine, heat again to 

 boiling, continue the heating for one minute • 

 set aside for teu minutes ; if no reaction by 

 separating suboxide of copper, it shows the 

 sugar to be present below o. 10 per cent. 



To show the presence of less than o. 10 per 

 cent, sugar in urine, it is necessary to use the 

 indigo-carmine test, consisting of two separate 

 solutions; a 0.2 per cent, solution of sodium 

 indigo sulphate in acidulated distilled water in 

 the one, and the other a 25 per cent, aqueous 

 solution of crystallized sodium carbonate, usetl 

 by adding 5 drops of the sodium-indigo sulphate 

 solution to a drachm of the sodium carbonate 

 solution, heat to boiling, when the solution will 

 acquire a green color. Add now 10 drops of the 

 urine, heat again to boiling, and keep the fluid 

 as near this temperature as possible without 

 ebullition for one minute, by holding the tube 

 in the flame withdrawing and successively re- 

 placing it at short intervals. If sugar is present, 

 the color will pass from green to violet, purple, 

 red, and finally straw-color, which remains 

 without further chauge in color, the latter color 

 being the indication for the presence of sugar. 

 By shaking the tube to admit oxygen of the air 

 and cool the fluid, the colors will return in the 

 inverse order to that which they appeared. By 

 this method urine containing o. 10 per cent, 

 sugar will change the test to a red, while o 02 

 per cent, changes it slowly to the straw-color 



