Chemistry and Physics. 53 
between walls of bed-rock, and passing only a short distance 
back of the fort. Ata point not far north of the targets, the 
fault divides; one branch continuing northward, across the 
spur, toward Farmington ; the other turning westward, running 
just back of that hopeless artesian boring, and following the 
upper edge of the gravel bench to the vicinity of the Warm 
Springs. Should the earthquake follow the former of these 
branches, the city, will not fare so badly as the fort; should it 
follow the latter, orfollow both, city and fort will alike suffer 
severely. 
What are the citizens going to do about it? Probably 
nothing. They are not likely to abandon brick and stone and 
adobe, and build all new houses of wood. If they did, they 
would put themselves at the mercy of fire; and fire, in the long 
run, unquestionably destroys more property than earthquakes. 
It is the loss of life that renders earthquakes so terrible. Pos- 
sibly some combination of building materials will afford 
security against both dangers. 
SCIENTIFIC. INTELLIGENCE. 
I. CHEMISTRY AND PHysiIcs. 
f 
been placed beyond doubt by the researches of Kopfer. The ques- 
tion to be solved is whether the elements of water or of calcium 
chloride enter in any way into the molecule. Stahlschmidt repre- 
Sents the formation of bleaching powder thus: 
OH\ ,/Cl) \ OH Cl 
(ca OH +(Gi ) =(caf Oui), +ea4 cit (4,0), 
Hence it must contain free calcium chloride. Odling’s formula 
‘he 
author sought to determine therefore, (1) th 
Ca(ClO),, of CaCl,, and of Ca(OH), in dry bleaching powder, (2) 
the existence of free CaCl, and (3) the composition of the residue 
after removal of the CaCl,. Pure lime was hydrated and analyzed. oS 
It yielded from 21-27 to 39-02 per cent of water in different sam- 
Pies. It was then exposed to chlorine until no farther increase 1 
