680 PHILOSOPHICAL TRANSACTIONS. [aNNO 1780. 



geon, who approved of the suggested experiment, and the patient agreed to have 

 it tried. 



Messrs. Nairne and Blunt provided an instrument for the purpose. It consists 

 o/a fine steel pipe, a little curved, cemented in a glass tube about 6 inches long. 

 At the top of the tube is a wooden funnel; and at the bottom of this is a valve, 

 which may be elevated by a silken string conveyed through a hole in the brim of 

 the funnel, and hanging down by the side of tlie tube.* The steel pipe was 

 passed into the inferior punctum, without pain or difficulty. The quicksilver 

 was then poured into the funnel, and let down the tube by pulling the string of 

 the valve. When the quicksilver regurgitated out by the superior punctum, the 

 instrument was withdrawn. The quicksilver lay in the sac and duct, without 

 exciting pain, about 30 hours, when it passed into the nose, and the patient 

 caught some of it in his hand. Mr. B. thought it best at this time not to com- 

 press the sac; apprehending it would discharge the quicksilver through the 

 puncta, and so frustrate the intention. 



On the 3d day the operation was repeated; when, on gently compressing the 

 sac, some of the quicksilver passed into the nose, and with it a pfece of con- 

 gealed whitish mucus. A small quantity of the quicksilver, on making the 

 pressure, returned through the puncta. At the 3d and 4th times of repeating 

 the operation, without any compression, at intervals of a few days, the quick- 

 silver passed readily into the nose. Mr. B. once introduced the point of a steel 

 pipe, used for injecting the lymphatic vessels. It is cemented to a tube of glass 

 18 inches long. This pipe is not so fine as that of the other instrument, yet it 

 was conveyed into the punctum without difficulty, and with little or no pain. 

 To gain a greater degree of momentum, he raised the column of quicksilver to 

 about 12 inches, when it flowed into the nose with a considerable degree of 

 velocity. From the time that the quicksilver passed into the nose, less fluid 

 trickled down the cheek than before. After the 2d or 3d operation, the swelling 

 or distension of the sac entirely subsided. The patient at the above date had no 

 discharge of mucus, and a tear but very seldom: the parts had a perfectly 

 healthy appearance. 



To ascertain the effects of medicines in diseases of the constitution, many 

 experiments, under various circumstances, are necessary; but in matters deter- 

 minable by a mechanical operation, the effect, as far as our senses can direct us, 

 is in general very plain and explicable. 



In the case related this is clear, namely, that previously to the injecting of 



* Mr. B. Las described the instrument as it was used; but he had since thought, that it would not 

 only be more simple, but do as well, without a valvular apparatus, the quicksilver being poured in 

 by an assistant. See pi. ; , tig. 1, where a is llic steel pipe, b tlie glass tube, ;uid c tlio funnel. 



