New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1861-04-28
SCIENCE, INDUSTRY, AND INVENTION,

SCIENCE, INDUSTRY, AND INVENTION,
METHOD OF PRoDucIsG RED, GREES, VIOLET, AsD
BLUE PHoIoGRArHs.-Niepece de Saint Victor gives
the followi ng directions for this purpose:
To make red pictures, the paper is prepared with
solution Of 20 parts Of nitrate Of uranium in 100 parts Of
water The paper is kept in thir solution from 10 to
90 minutes and then dried in the dark by heat. Ii
NAV be prepared several days before using. To copy
pictures they must he exposed from 10 10 minutes in
the direct sunlight and from TO hours in cloudy
weather according the strength Of the Light and the
inlen,ity OF the negative.
Tic picture s taken from the copying.!rame washed
few seconds with water at 80 or 60 deg then dipped
in solution of red prussiaie of potash 2 cent.
After few minutes the picture takes on beautiful
red color it is then rnsed till the washwaier remains
perfectly coloress and dried
For the green color red picture obtained in the
manner already specified is held for about one minute
in q solution Of nitrate Of cobalt, and dred by heat
without washing, whereupon Ito green color appears
and is fixed by immersing the paper ior few seconds
in a solution composed Of four psrts Of sulphate Of
iron and four parts Of suphurc acid with hundred
parts water-then rinsing with clear wafer and dry.
ing by heat.
Violet pictures: The paper prepared with nitrate
Of uranium is suitably exposed in the copying frame,
then washed in warm water and brought into
solution of Chord Of gold q per cent When the
picture has assumed beautiful violet color il s washed
in several waters and dried.
To make blue pictures, the paper is prepared with
solution of red prussiae Of potash GO per cent, dried
in the dark, and put into the copying frame. This
paper can also be prepared several days before using.
When the portion exposed 10 tho light has become OF
faint blue color il 10 taken from the frame and placed
during five or seconds in saturated solution Of
corrosive sublimate. The picture is then washed
with water and solution Of oxac acid, saturated in
tie cold but warmed upon application 10 1902 r., If
poured over it, The picture again washed with wa
ter three or four times and then dried.
CoAL-AsH CEnIsT-According 10 DR.. Julius Leh-
man Of SaxoDy, the ash Of brown coal mixed with
sand and lime forms q composition which is well
adapted for the hOorngs Of stables, ooaehhOuses, Ell
trance-has, and may also be used for the roofs of
arched buildings. The mixture is composed Of burnt
lime and clean sand two and onehalf parts Of each by
bulk, and eight parts Of rather eoarscly sted ash.
The lime lie to be SACKED dry-tLe sand and ash
mixed together, aud water is added till the whole
forms tolerably stiff paste. IL is then laid on flor
floors from FIVE 10 Elk inches thick and smoohed with
the trowel For roofs layer Of three inches is sutf
Gent Floors Of stalls and carage-houses after hav
ing dried for two three days, are improved by
coating Of tar which prevents the absorption Of water.
O-pant an excellent substitute for II adheres
equally well, and the floor thus painted can be kept
clean by washng with soap and water. Doubtless the
ashes Of anthracite and btumnous coal will be found
10 serve these purposes well those Of the brown
coal used in Saxony.
INVESTIGATIONS UPos MISUNDERSTANDING has in
sttuted experiments upon the capacity OF various kinds
Of smoking TOBACCO TO retain fire. and continue burning
without u current Of air. II Is well known that the
ashes Of plants contain suphuric hydrochorc, phos
phorc and carbonc acids salts Of potash coda and
line beside silica, both free and combined, &C. After
the eaustic lime has been converted into carbonate,
water dssolves from the ashes beside alkaline sui
pilates and Chords, very frequently slcates and car
donates Of potash and coda. In such sulphurc
and bydrochlorc acids are not sufficient to lutte with
the akali. The ash Of tobacco which retains fire al
ways contains carbonate Of potash. Soda does not
in tobacco and in general tobacco retains fire the
longer the strongly alkaline It's ash is. The ashes
Of tobacco which refuses burn except by continued
putting, yield TO water no carbonate of potash; the
potash they contain exists in combination with suphu.
ric and bydrochloric acids. Such qualities Of tobacco
hold Gre after potash salt Of some organic acid (maic
ctric oxac, tartaric is incorporated with them in
ssch quantity that in the ashes potash is found 10 ex
cess above what ia neediu to unite with suPhurc az
hydrochlorc acids
On the contrary, goodsmohing tobacco loses its power
of continued smolderng if salts Of lime, magnesia, or
ammonia are added 70 tuch an extent TO occasion an
excess Of mineral acids over the potash originally
present.
1t might be supposed that the presence of the nraes
aided tobacco in holding fire. There is no doubt that
they DO contribute TO this result but their action ls
secondary and depends upon the formation Of car
bona,es TIE author las in fac, previously shown that
the best smoinc t,bsccoes contain the smallest quaI-