488 Scientific Intelligence. 
cylinder, and the steam arising from the boiler was condensed in 
a serpentine condenser. The number of calories utilized by the 
apparatus was deduced from the weight of water distilled per 
hour; and hourly actinometric observations gave the number of 
calories that were received by the apparatus. At the same time 
number of calories utilized and that received were expressed in 
great calories (kilogramme-degré) received in one hour upon 1° 
‘of surface normal to the solar rays; their quotient gave the effi- 
ciency of the apparatus. The following table expresses the princi- 
pal results obtained: 
Average Value of Results obtained during 1881, per 1™4 per 1%. 
Maximum 
Cal. Cal. 
Heat received directly ------- ooo eOlGL 945°0 (25 April.) 
Heat utilized by apparatus- .----- 258°8 547°5 (15 June.) 
Mean of efficiency -....--------- °491 0°854 (14 June.) 
Under the most ‘favorable circumstances, that is to say, with an 
sulphate, as has been supposed. Analysis showed the presence 
of lime and magnesium oxides with water and organic matter. 
Eliminating accidental impurities and considering the scale an 
impure lime salt, it gave the composition H,O 7°95, CaO 24°32, 
organic matter 67°73. e organic acid was separated from the 
is . 5 . . . . 
finely pulverized scale by dilute sulphuric acid in quantity short 
of saturation of the calcium, and salts of zinc, lead, silver, magne- 
sium and calcium respectively found with it and subsequently 
analyzed with results very closely agreel o the assumption 
ng t e 
that the sorghum scale is a two-thirds metallic calcic aconitate 
Te Ss ees sr ete ee 
gi Bi ais Eee oe meaa ae 
yi AR a 
CPEs Eee aye oe ee rae ee 
