COEKESPONDENCE. 279 



and over again vaunted its supreme necessity for obtaining the best 

 results with high powers, yet Messrs. Powell and Lealand, who con- 

 structed it, did not exlaibit it in December last in connection with 

 their new Tnytli ^^^ sV*^ immersions. And though, on the other hand, 

 Dr. Pigott says, " It increases magnifying power and penetration, and 

 enables us to use a low objective instead of a much higher one giving 

 as much power " — Messrs. Powell and Lealand did not use it at their 

 recent exhibition of their new and remarkably fine ^th immersion — 

 when surely if they had believed in it they would have used it. 



I think, sir, many of us do not join in the chorus of jubilation in 

 honour of Dr. Pigott, because we feel a sort of je ne sais quoi, which 

 a little frankness in answering these inquii-ies may possibly remove. 



I remain. Sir, 



Your obedient servant, 

 John Matall, jun. 



How TO PUT AN End to Me. Wenham's and De. Pigott's 



CONTEOVEESY. 



To the Editor of the ' Monthly Microscopical Journal^ 



Sir, — Instead of carrying on perpetual literary battles about 

 Dr. Pigott's " bead theory," why, may I respectfully ask, don't the 

 parties for and against, fight at once with their own object-glasses ? 

 — fitting umj)ires being chosen to determine which side is victorious. 

 As Dr. Pigott and Mr. Wenham happen to be foremost in the fray, 

 let their finest object-glasses, their ith, and ^th, and -^^^ih, and y g^th, 

 and ^V*^5 ^^ fairly tested one against the other, not necessarily on 

 objects that "ought" to show the beads, but on ordinary standard tests, 

 such as P. angidatum, P. S;pencerii, N. rhomhoides, Acus, &c. Expe- 

 rienced microscopists need not be told the points of a good object- 

 glass, and can trust their own eyesight when bringing object-glasses 

 to bear on the above tests ; and they may rest assured that those which 

 will show them best, will also show the beads on Podura, if there are 

 any to be seen there. Thus there might be a fair chance of ending 

 this paper warfare ; a result much to be desired, as it is scarcely 

 generous or in good taste to write what involves constant aspersions 

 on Mr. Wenham's character and judgment — who, as an amateur, has 

 done more for the microscope than any man living, and in respect of 

 whom scientific antagonists might surely forget their differences in 

 gratitude for all that he has accomplished to further their favourite 

 pursuit. As I have no reason to be ashamed of my views, and indeed 

 feel convinced that a large body of microscopists will uphold them, 

 I shall not scruple to give my name and residence. 



Believe me, yours faithfully, 



J. J. Plumer. 

 The Hates, Stroud, Glouoestekshibe, 

 Nov. 12, 1873. 



