New-York tribune., 1879-06-07
SCIENCE FOR THE PEOPLE.

MANY-TOED UORsES.-ProfesSOr ". " M"is
has brief bat interesting article on "PoDdaetyIe
Horses recent and extinct" In the June number OF inc
American Journal Of Science aud Arts. In which he cites
several curios instances Of extra dgs in the loot OF
the modern horse and that these reversonsto an
older type far more numerous than is conmoh''
supposed. As 10 the ancestors OF these anmaiS sH
the Professor there can he no doubt America Is the
original home OF the horse, and during the Whoio Vi
Tertiary time this continent occupied with equine
mammals OF many and various forms. Although HI
these became extinct before the discovery OF TINS couh
try their abundant remains mark out tho geneaiogy oi
the horse in an almost unbroken succession OF FORMS
II we examine the remains OF the oldest representatives
OF the horse this country shall ind thn thcse ~
mails all polydacye and Of small SIZE AZ Tue
was continued toward the present era, there was sr'
ual increase in sze and dminution in the number OF
toes until the present type OF horse WIS produced Inc
original of the horse not as yet
doubedly had five toes each foot The Oldest mem
her Of the group now known the Eobippus winch nau
four well-developed toes and the rudimeht oi ao'u
on each forefoot, and three toes behind Inls ahha
was about "a large fox. and Its renaihs are from
the Coryphodon beds the base Of the Eocene In
the next higher division Of the Eoceno another equine
genus Orohippus makes its appearance. IL resemDled
s Predecessor I'm sze hut had only four toes In front
and three behind At the top of the Eocene third allied
genus has found Ephippus)that closely resembed
Orohippus In its dgits but differed In It's teeth. Near
the base Of next formation. the M0cene, another
equine mammal, Mesohippus, occurs This animal was was
about as large sheep and had three usabe toes ana
the splnt of another on each ioreo0t, win but hrec
toes behind. At a somewhat higher horizon nearly
allied genus MiOhppuS, has been found which mas the
spnt bone of the fh digit reduced 10 short
remnant In the PhOcene above three-toed horse
RrntOhippus) about large ds donkey was abundant
and sti higher near ally OF the modern horse VIII
only single toe ON each foot tPohppusl. makes lis
appearance. A true EqAus, as large as the existing
horse appears just above this horizon ana the series Is
complete.
A NEW FXPLOsIYE-The new explosive for
military usc recently introduced in Austria appears 10
have remarkable properties. II consists OF NoOris tx
plOsive gelatine formed by dssolvng guncotton lh
nitrO-gyoernel. with camphor added in varying pro-
portions n0mnay per cent?. An Interesting account
of experiments made at the works OF Z'mky with TINS
explosive Is now appearing in the RecHe fAr'Her'e'
From experiments iron plates it appears that, weight
for weight IL is 25 per stronger than the best
Ko,elculir dynamite. The freezing of the charge ana
the prming cartridge does diminish the nnamma-
bifv and SCATTERING force. The explosive s no sensi.
bis altered by brug under current water oiy-eLh'
hours. Fired at in the soft state with re al tweny
five metres distance. rcsists the shock; but not II
frozen and placed against iron (or against wood II fp
superiority, for mtary purposes to ordinary GXpiosNe
gelatne and other explosive Is very marked his ne"
explosive IS known as blasting gelatiue'
THE GARY MoToR.-In a late number OF The
Journal ofe Franklin Institute PROBES Morton dis
cusses claims Of this ALLEGED discovery He describes
II a. device which comes before the public in double
character First, as perpetuamotion machine, which
is to do work without transformation of energy, in
which light he dismisses II as fraud blunder and
secondy as the exponent OF certain alleged new facts
claimed to have been discovered by the Inventor thr
Gary) with reference to the action OF magnets In ths
category Nj. Gary's claim OF discovering neutral
line" around magnets is placed. Respecting this So
called discovery, Professor Morton finds that Mr. Gary
of VIII hel hrp
noticed long the time OF Sir Isaac Newton, and
which are described by Hmm the "PIncipa" Professor
Morton holds that all Of Mr.. Garys experiments that
Will work may readily explained by the wellknOwn
principles Of magnetic Induction by reason Of which
piece OF soft iron magnet inductycly magnet
Ized by the and rests upon it, and thus, as New
has II, contracts the virtue Of the magnet and
neutrazes s action exterior bodies The Professor
that Mr. Gary presents no evidence to prove the
OF the existence oi neutral Inc ABOUT nagnct
but that the contrary, the very experiments which
he cites proof OF 1t 'smpy demonstrate tat IN GER
tain relative positions the opposing deOhs OF pefha-
nent gnet aud piece OF soft iron ndgnetzed by III
ducton irom II neutraze each others effects upon
third magnetic body, such as piece Of IRON or COM
pass-needle."
LIGHTNING RoDs.-Mr. X. S. Brough has
been discussing in The Philosophical Maga-ine the
proper sectional iron and copper lightning rods
so far as mere conducuvity ia concerned a compare
lively thin wire of either metal would suffice for the
oftiest conductor but such thin conductor would he
dangerous because it would be fused by a heavy dis
charge OF lightning Iron Is more liable TO be fused
than copper aud the point MI Brough sought to de-
ermine was the relative sectional OF rods Of the
metals so that neither would be liable to fuse
than Ordinarily it is stated that the iron rod
should four times the sectional area OF the copper
rod Mr. BrOugh shows that these areas should be as
to 8 or since rods invariably circular. and cir
cuar areas 70 each OtuCr as The square OF thelr
dlameters the dlametcs of iron and copper rods OF
eulal effectiveness should be in the proportion of 163
To |. Iron is therefore much the cheaper metal iOr
lightning rods.
JAVA VoLCANOES.-The latest accounts from
Singapore that the volcanoes in both the eastern
and the western districts OF Java In ml activity.
broad river OF fiery lava flowing from the crater OF
smeru down the southern coast, Illuminating all the
neghbOrhood at night with its ruddy light. The Gedeh
mountain was cjecung enormous amount OF clnders
wAcn were completely covering all the surrounding
district