Intelligence and Miscellanies. 363 



very wasteful manner. It is even thought that the earth 

 which has already passed through their hands, would, by care- 

 ful management, yield another product as great as that which 

 they obtained in the first instance. Very little of the dust is 

 collected, nor is the business reduced to any system. We 

 have great need of a few ingenious Yankees, to invent labor- 

 saving and economical machines for us." 



5. PettengilVs Stellarota. — The Rev. Amos Penttengill 

 of Salem, Conn., has contrived a very ingenious instrument 

 for the use of students of astronomy, to which he has given 

 the name of the stellarota. It is in fact a moveable plan- 

 isphere^ and affords, at a very cheap rate,* many of the fa- 

 cilities for studying the heavenly bodies, usually supplied only 

 by celestial globes. 



Celestial maps are apt to produce much confusion in the 

 mind of the young learner ; and since the appearance of the 

 heavenly bodies, which they represent, does not correspond 

 to their actual position at any given time, his progress in 

 studying the constellations is little aided by them. On the 

 contrary, the celestial globe is capable of such an adjust- 

 ment, as to bring the stars, as delineated on its surface, to 

 correspond with the actual appearance of the concave, at 

 the very moment when he is viewing it. Various astronom- 

 ical problems also of the most instructive kind can, as is well 

 knovvn, be performed on the celestial globe, which cannot 

 be wrought on the common maps or planispheres. But the 

 stellarota is capable of being adjusted to the time and place 

 in the same manner as the globe, and affords the means of 

 solving nearly all the problems that can be wrought on the 

 latter. 



This instrument consists of a disk or circiilar card seven 

 and a half inches in diameter, fixed into a circular opening 

 of the same dimensions, cut in a thin rectangular slab of 

 wood. The disk is turned on its axis by means of a thumb- 

 piece attached to the centre on the back side of the slab. 

 The centre of the card representing the projected pole of the 

 earth, the various circles and constellations of the spheres, 

 take their respective stations around it. In order to under- 

 stand the manner in which these are severally laid down, let 

 us take an orange^ and mark on its rind circles representing 



■" The price of the instrument neatly framed, does not exceed two dollars. 



