75 
with the i inch and higher powers it is always a trial of 
patience even when the position of the object has been care- 
fully registered with a lower power, and you are sure that 
the object is central in the field. Perhaps with the achro- 
matic condenser some of the difficulty may be removed. 
It will be remembered that about 20 years ago the late 
Mr. Rideout presented to the Section a machine for pro- 
ducing minute writing. The instrument was lent by Mr. 
Rideout to Mr, Dancer, by whom it was recently sent to the 
Society. It seemed to me that as this instrument was pur- 
chased by Mr. Rideout at the great Exhibition in 1862, it 
might be the same with which the wonderful piece of writ- 
ing, or perhaps it should be called engraving, referred to, 
wa-s executed. I therefore wrote to Mr. Dancer for infor- 
mation on this point. In reply he says : — The microscopic 
writing on glass of the Lord’s Prayer referred to in your 
letter was at one time in my possession and was, I believe, 
presented by me to the Microscopical Section. It was 
obtained from Mr. Webb, and he was the same person who 
exhibited the microscopic writing machine at the great 
Exhibition of 1862. Mr. Webb died about 10 or 15 years 
ago, but I cannot give the exact date. I have a very strong 
impression that Mr. Rideout obtained the machine from him, 
which was sent by me to the Society. If able to find Mr. 
Rideout’s letter it may confirm this.” I have not received 
the letter, but as what Mr. Dancer says confirms the im- 
pression I have of what passed at the time, there can be 
little doubt that the instrument is the one used to produce 
the writing referred to. 
Under the microscopes I have arranged two other slides 
of minute writing which have been lent to me by Mr. Arm- 
strong. These are not very minute when compared with 
the one first referred to, and which I have placed under the 
third microscope where you will see the object with an eighth 
object glass. Even with this great amplification the words 
