298 On Liquefaction and Cold. 



Mn(N0 3 ) 2 .6H 2 withNa 2 CO 3 .10H 2 O 



Zn(N0 3 ) 2 '.6H 2 " 



37 



Cr s (N08)«.18H 2 0," 



Fe 2 (N0 3 ) 6 .18H 2 „ 



J) 



>? ?; 



» 



?> » 



)) 



Initial 



Lowest 





temp. 



o 



18 



temp. 



o 



-14 



Loss. 

 32° 



- 2 



-26 



24 



20 



-16*7 



36-7 



- 1 



-21-5 



20-5 



- 3 



-22 



19 



13-5 



-17 



30-5 



10-5 



-17 



27-5 



- 3 



-24 



21 



It will be seen from these and the following results that the 

 minimum temperature is not independent of the initial tempe- 

 rature ; it was also found that the lowest point varies with 

 the proportions taken : 



Initial temp. Lowest 

 1st. 2nd. temp. 



IOHoO 45° 22°* -12 ? 5 



Pb(N0 3 ) 2 





with Na 2 C0 3 



Fe 2 (N0 3 ) 6 



.18H 2 



j? j; 



A1 2 (N0 3 ) 6 , 



. 18H 2 



?> ?; 



39 32 - 4 



37 32 - 2 



With the nitrates of magnesium and calcium the tendency 

 to metathesis is so slight that the liquefaction is not rapid 

 enough to produce any great degree of cold; and with an ini- 

 tial temperature of —2° there is no liquefaction whatever. 



The time allotted for the completion of my graduation 

 thesis, of which this paper gives the substance, rendered it 

 necessary to suspend for the present the continuation of these 

 experiments. This work was undertaken at the suggestion 

 of Professor Ordway, to whom the subject has been one of 

 interest for some years, but whom the pressure of other duties 

 has prevented from pursuing an investigation. He has, 

 however, given considerable thought to the matter, one of 

 the results of which is his theory of the " diffusion of solids." 

 His predictions that there may be liquefaction without 

 chemical reaction, and that the product obtained from the 

 mixture of salts is sometimes hydrated, were both confirmed 

 by the results of my work. He devised the calorimeter 

 which was used ; and I am indebted to him also for valuable 

 suggestions and advice. 



Mass. Inst. Technology, June 3, 1881. 



* The temperature of Na 2 C0 3 . 10H 2 O could not he raised so high as 

 that of the other salts, without melting. 



