New-York tribune., 1904-10-08
MECHANICAL MARVEL,
Can Rouland's Famous apparatus
Be EqaalIed?

Baltimore. Oct Cspeci.l).-The scientific world
s. interested in an important mechanical opeFauOn
Al the physical laboratory OF Johns HOPKINS
University. Should the work be failure there
VII Dc some serious Inconvenience 70 the various
fslds Of science in which spectToscopy plays an
important part
The successful conclusion TO the operation viii be
rhs answer TO question frequently advanced since
she death Of Professor Henry A. Rowland-whether
fhe secret OF cutting the thread for the finely
ground screw upon which the manufacture OF the
fanous Rowland spectroscopie gratings depends
he's been lost. Since Professor Rowlands death
ahere has been decided disinelination the part
Of the physical faculty TO talk about the matter.
and many persons conceived the idea that the
secret OF cutting the delicate screw had passed
away with the death Of the great scientist and
mathematician
Now. under the direction OF Lewis z. Jewell. as
Eistant in practical photography and spectroscOpy
Sn Johns Hopkins University, and with the
trained hands OF Foreman Charles Childs Of the
mechanical department. the FIRST new screw since
the death Of Professor Rowland Is to be cut, ana
- successful the new machine Il 20 be added TO
the three other machines in the eouai-teulperature
vault o. the phy steal laboratory.
The question as 10 whether the making Of the
screw Is secret or rot is interestlcg one. the
doubt concerning which has been deepened by the
Inevitable process Of circumstances which came
about three years ago.
Professor Rowland. who was OF an extremely hue
mechanical turn OF mind. well a mathemati-
tidn GGFAseu a meLlOQ OF CuNLlIS the screw anu
grinding it under water. which he taught 10 his
head mechanic. Theodore G. Schneider. and the
2Rtter became exceedingly proficient IN making tie
Ehreads and the ruling machines. and then in eut-
Fing the gratings. The department while not re-
susing information 20 other universities managed
keep the secret OF cutting the screw within its
own walls.
For years then. ths grating machines In the Hop.
.bIns physical laboratory ground away in mOnotO-
nous regularity. their fine diamond points slowly
but surely cutting their thousands of lines to The
inch upon polished plates Of steel or glass
entity before a new physcis. could be trained to
direct the work-Professor Rowland passed away
suddenly, and even Professor Rensen was inclined
10 believe that the of making the valuah BILE
eIaHg screws had passed away Win me scehtsL
!iopkins vaults would have been absolutely price
Since then there has been speculation pro and
con as 80 the Likelihood OF the successful cutting
Of a screw BY any OF those who survived the great
- After schneider's death Charles Childs who had
zhe laboratory. was entered under Professor Row
"a this Short time and with working unde= Skilled
scientist now there is felt be little doubt that
The principal point IN making the screw is grind
rate, as there are many thousands OF lines cut
upon the plate within the space OF inch, ana the
10 shift the diamond point small traction OF an
inch at each revolution The gratlngs are or great &
!. would be irresrie7able TO the scientific world
The significance OF the approaching test lies in the
Sact that for certain classes OF specroscopic work
N grating is preferable to instrument composed
.spf pTdsms. A grating is concave mirror on whose
- surface hne parallel lines have been engraved
such articles have been made elsewhere, but those
produced by the Rowland machine are universally
recognizes as far superior TO ell others That piece
of mechanism Is capable OF ruling 100 lines TO the
;nch. When Lord Kelvin IN this country sew
crsl years ago. he made special trip 10 Baltimore
70 have chance TO see this marvel The most i'm
znrtant feature OF this ruling machine is
that controls the movements OF the craving tool
and the question arises whether new ones can
ever be made whose work will match that OF those
maze directly under Professor Rowland's eye.