142 Newellian Sphere: 
Eighthly, The propriety of the general steps in the ope- 
ration for calculating the latitude se longitude of places on 
the earth’s surface, from observations of the heavenly bodies. 
Ninthly. The phenomena of sales and siderial time, and 
the propriety of the intercalary day for each fourth year, with 
its suspension, each fourth century, according to the Grego- 
rian or new style. 
The — ng are some of the principal .astronomical 
phenomena, mechanically illustrated by the Newellian 
Sphere, a " contrivance, considering the object for which 
it. was designed, more perfect, it is believed, than any 
that has heretofore been devised On the value of machines 
of this description for the purpose of instruction, it is unneces- 
sary long to dwell. Their utility is sufficiently agi 
ed in the many attempts that have heretofore been made t 
construct y persons well skilled in the science of  as- 
tronomy. The whole system of planetary bodies is condens- 
ed, as it were, into a compass so small, that the mind easily em- 
braces every part, and sees at a se glance the principal re- 
tive motions and changes which the mutual actions of those 
bodies have been found to produce. It will not, indeed, be 
pretended, that the machine will yield, at one view, a clear 
eonception of the celestial motions, or e: the operations 
of those laws which the doctrine of matter unfolds, and a 
which human reason has reared by far the most stupendous 
fabric of its power. A perfect knowledge of so extensive and 
iatricate a science as that of astronomy, is by no means so 
easily to be attained. There is indeed no more a ‘“ royal 
road” to astronomy at the present time, than there was to 
geometry, in the days of Pythagoras. An unwearied zeal— 
long and constant application—are the only means which can 
insure to the mind a clear and adequate dea 3 of the 
truth and application of its sublime theories. rofess- 
ed scholar, therefore, one who has time to — to che 
researches, a machine of this description will not be so es- 
sentially beneficial: his meemiestars of mechanics and 
physics, will easily prepare him for a knowledge of the celes- 
tial motions, all of which he will readily comprehend as he 
gradaaiii advauces in his labors. But to those whose dif- 
