158 The Microscope. 



Considering that these bacilli, in the course of prepara- 

 tion for use under the microscope have passed through several 

 mechanical and chemical processes, any one of which would 

 kill them if they were ten times as tenacious of life as they 

 really are, and that their stained bodies are hermetically 

 sealed in glass and Canada balsam, nothing could be more 

 ridiculous and absurd. And yet this is only one specimen of 

 the " rot " which passes current as science in the daily press, 

 and whose only effect can be to needlessly alarm the timid, and 

 retard popular scientific information. — F. L. James, in National 

 Druggist. 



NOBERT'S RULING MACHINE. 



The world renowned ruling machine of the late M. Nobert 

 was exhibited at the last meeting of the Royal Microscopical 

 Society. It has been purchased by Mr. Frank Crisp, one of the 

 secretaries. The foundation of the machine is the ordinary di- 

 viding engine used in the graduation of circles and sextants ; 

 this, by a vast amount of delicate superposed mechanism, is 

 made to rule lines at a very minute but determinal distance ; 

 strange to say, the lines are not straight ones, but portions of a 

 large arc ; the lines, however, not exceeding one-fiftieth of an 

 inch in length, the curvature is not perceptible. The diamonds 

 used for ruling are worked to knife edges, in some instances 

 ground, in others clipped, but made with such delicacy that 

 microscopical examination fails to detect any serrations; in this 

 and the glass employed would seem to lie the secret of the fine 

 quality of lines produced by M. Nobert. The note book of the 

 inventor accompanies the machine, and in it the performance 

 of each diamond has been recorded, and much useful informa- 

 tion that will probably enable the machine to be used. Ex- 

 perts who have examined the machine since it has been in 

 England do not consider the mechanical contrivances the best 

 that could have been devised; but the fact nevertheless re- 

 mains that Nobert contrived to execute rulings which have not 

 been equaled. The resolution of the nineteenth band, in which 

 the distance of the lines — according to Dr. Piggott — is 112.595 

 to the inch, and formerly supposed to be impracticable, is now 



