New-York tribune., 1876-02-05

CoXvFRsIoN or BHUCISg INTo SrRYCItN1SE.-
S0nnenschein has shown that bruc,nc may be
converted into strychninc by the action Of nitric
acid and calls attention 10 the fact that this dis
covery may be Of practical interest in toxicooeica
Investigations since brucine might be- converted
into stryclnue in course of ,hc examination.
TIMING IRoN TACKs.-According to Wiley, the
process is to trturato chloride Of zinc with large
quantity Of OIL and heat il in oscillaiing ycsSc!
and ~ soon as it has reached the proper tempeIa-
tnre throw in the tacks and the necessary quantity
of metallic tin, and after few seconds dip them out
with wire gauze and cast them into water.
Brown STAIN FOR OAK.-Welger recommends the
following as afiordng cheap coating for wood
and which is very adheIent, even when exposed to
the weather. Brush the wood with solution OF
persuphate of iron OF % 10 2i2 Bauin6. The blush
gray tint it acquires drying changes 10 agree
able light brown shade with linSfed oil varnish.
solution of prOt0suphatc of iron viii answer well
AS one of the perSulphatc. dark brown shade may
be impaired by subsequent coating with y per
cent solution Of permanganato OF potash and then
with lnseed OIL.
DEsILvERIZATIoN OF ARGENTTEROUs XINC.-The
desilyerizatiOn process introduced by Parkes III
1880 but subsequently neglected In consequence OF
the difficulty of recovering the metallic zinc so as to
be reGmployed in a continuous process, has been
The argontiferous zinc crust is now allowed to cool
In an iron ban. then placed in the liquatng
furnace. where, by gentle heating with fun access
of air il is deprived of the greater part of IL lead
By this means the zine Is Thoroughly oXihlzed and
converted into the so-calied zinc Dust winch IS then
distilled between LAYERS OF powdered coke with the
production of metallic zinc, free from silver, on the
one hand, together with residue containing the
whole of the silver, along with any lead remaining
III the zinc dust.
PHoTOGRAPHIc POWER or ARTIFICIAL LIGHT
Comparative tests Of the Photographic effect Of light
from different artificial sources have been made by
Richie and Bardy Plates senstized with
bromide Of silver and exposed for 60 seconds al Il
distance of . inches from the light while screened
from its action by ten unequal layers of waxed
paper the first four inches long, covering the whole
plate, and each successive layer beng one-tcnth
shorter, the last beng fourtenths Of inch long.
The effects were compared by noticing after deyel-
opment the number of layers of paper through
which the light had acted. Thus il was found that
the Oxyhydric light penetrated but one layer; the
Drummond light three that Of zinc burned in oxy-
gen. four OF the magaesinm light, hy.; of a jet Of
nitric oxide passed through flask containing hi
snlplnle of carbon, ak of jet of nitric oxide ia
vessel OF burning bisulphIde OF carbon. six and
seven Oi Jet of oxygen IN vessel of bisulpllide
OF carbon, seven; OF OF oxygen IN IA vessel of
burning sulphur, eight The INTRODUCTION Of oXy-
gen into jet OF burning sulphur, il produced tho
greatest effect upon the bromide Of silver seems TO
merit further tosts as TO its practical value.
THE MECHANICAL THEORY or CYcLoSEs.-Among
the treatses OH the mechanical theory Of the move
ments of air in revolving storms both hurricanes
and tornadocs, but few have such practical value as
that Of Colding, published in Danish in 1871 trans
lations of which have recently been prepared by
Ham of Vienna, and Able of Washington by means
of which the Englsh-reading public is introduced to
series Of novel Investigations into the flow of
liquids which form very acceptable addition to
our knowledge of the subject According TO Cold
ing, the laws governing the movement Of water may
with certain restrictions, bo applied to tho move
ment of tho air. and after having an engineer for