PROCEEDINGS OF THE SOCIETY. 
577 
the combination of the lenses, but there was no doubt that Chevalier’s 
lenses were uncommonly good. 
Mr. Karop said there were several other points which suggested 
themselves, but it was too late then to go into the subject. 
Mr. Washington Teasdale said he chanced to have worked up through 
every one of the series which had been mentioned, but he considered 
them practically obsolete from about the time that the Society of Arts 
brought out their 3-guinea Microscope. The Continental Microscopes 
became so popular because at that time medical men could not get a 
good English Microscope under about 25 l., but one of the German 
instruments was supplied with four powers of really good quality for 
about SI. Of course the question was too large to go into at that late 
hour, or he could have shown how it was that these Microscopes con- 
tinued to be used, although he considered them to have been thoroughly 
and entirely superseded by the modern English forms. 
The Chairman said there was no doubt that many other points might 
be brought out if only time permitted. 
Dr. Nias said he was unwilling to occupy more time at that period 
of the evening, but he did not think that after all there was any sub- 
stantial difference between them on the questions raised. For his own 
part he should never attempt to say that the Continental form was better 
in all respects than the English model ; what he had wished to do was 
to bring out some facts as to the history of the development of the 
Continental form, because, though much had been written about it, 
nobody seemed to have shown how it came to be adopted. 
Mr. Ingpen said the rotating stage was adapted from the Ober- 
hauser model. 
Dr. Dallinger said that a very important consideration would come 
out of this if it were looked at from a practical standpoint. By this 
process of revolution the whole of the body was made to rotate about 
the centre of the object, and if the whole of the parts were made with 
absolute accuracy there might not be any very great objection, but in 
cheap instruments they could not of necessity afford to make them 
accurate, and, therefore, if they attempted to rotate the upper portion 
they very speedily got it out of centre and most serious optical errors 
were in this way introduced. 
Mr. Ingpen said no doubt the Continental form had its purpose but 
that was frequently overlooked because nobody ever seemed to look into 
the subject if he could help it, and because here we were accustomed to 
attack the whole subject from an entirely different standpoint. He 
thought it would be a great pity to ignore the value of these old models 
or to pass over their history, which was in itself extremely interesting 
and instructive. 
The thanks of the meeting were then voted to Dr. Nias for his 
paper. 
Mr. C. Rousselet said that he felt he could not at that late hour 
trouble the meeting with his paper “ On Floscularia pelagica and other 
Botifers ” (see ante , p. 444) ; he would therefore content himself by 
merely mentioning the names of the species described and would hand 
the paper over to the Society for publication. 
