288 C Bar us — Compressibility of Colloids. 



nary temperatures water and albumen on graphic representa- 

 tion show nearly the same compressibility, so far as the present 

 method goes ; at 100° gelatine is throughout less compressible 

 than water, the difference being as large as 10 per cent. 



In Table 2 I have computed the compressibilities (3 for each 

 of the three cases, at different temperatures 6. Observations 

 were made in triplets, beginning and ending in the same low 

 pressure at each temperature. This eliminates change of tem- 

 perature due to cooling of the water bath. The colloids were 

 kept liquid throughout ; though the albumen turned white 

 gradually at the higher temperatures, it did not at once set 

 firmly. 



Table 2. — Compressibility of water and of colloidal solutions of gelatine and 



albumen in water. 



e,L 



23-3° 



17.4cm 



Water. 

 p 



5 

 160 



/3xl0 6 



48 



52 



Gelatine 10$. 

 6, L p f3 x 10 6 



21-4° 5 

 20'3 cm 177 51 



Albumen (Natural). 

 6, L p p x 10 6 



22° 5 

 123 cm 128 50 



100° 



Ig.pm 



10 

 198 



23-6° 

 20'3 cm 



5 

 165 



50 



28-8° 

 12.3cm 



4 

 181 



50 









25-8° 

 20-3 cra 



12 



190 



52 



27-5° 

 12'3 cm 



4 



178 



47 





29-2° 



20.4cm 



12 



188 



53 



49-5° 



l 2 . 4 cm 



4 

 192 



52 





32-0° 

 20'4 cm 



18 

 187 



52 



53-5° 

 12 .4cm 



4 

 176 



1 

 190 



50 





36'8° 

 20.4cm 



30 

 201 



30 

 186 



49 



5 / 



12'5 cm 



50 





43-5° 



20;5 cm 



50 



59-6° 



12.5cm 



1 

 203 



48 





53-3° 



20'6 cm 



100° 

 21-l cm 



31 

 181 



52 



*63'6° 



12.5cm 



2 



187 



55 





10 

 185 



51 



*67*5° 



12'5 cm 



11 

 195 



52 





100° 

 21-l cm 



12 

 197 



51 









The results are not unlike the preceding set. The com- 

 pressibility throughout remains very nearly that of water. 



* Coagulating but not set. Threads break off, observation difficult. 



