305 Scientific Intelligence. {Ocr. 
sought after, which consists in the construction of a valve applicable 
to this part of science, that must be in a great measure very com- 
plete. I mean those after the manner of the valves of the human 
body. I believe it is an indisputable maxim that the nearer we 
approach to the mechanism of the vital frame, and to the operation 
of nature, in all of our endeavours, the nearer we conceive and find 
we reach to perfection. 
The valves of the human body every anatomist must be fully 
aware are constructed on an inimitable priuciple; and for what an 
infinite space of time do we often behold those most important organs 
performing their office uninterrupted and unimpaired. I cannot but 
imagine that this plan must have been contemplated by many, and 
even put into practice ; but being unable to discover any account of 
its being attempted, I should feel myself under a great obligation 
to you, or any of your correspondents, that would give me the 
necessary information. 
A few weeks since I constructed a temporary model of a pump on 
the plan alluded to, by fixing the valve within a piece of large 
barometer tube, by which means its action could be plainly per- 
ceived: and as I conceive many of your ingenious readers may not 
perfectly comprehend the manner in which the valves I alluded to 
are constructed in the human body, I have subjoined a slight sketch 
of them, and hope it may prove sufficiently. illustrative. It is 
greatly with the hope that some more able mechanic than myself 
will devise a proper plan for securing the valve, and discover those. 
materials that will best answer the purpose, and erect one ona large 
and useful scale. 
c 
a b 
iit 
coe 
rh aD is 
The materials of which the valve itself must be composed appears 
to be the greatest obstacle to their general employment. | firmly hope 
that this is within the reach of many : and if this paper should be the 
means of drawing any able person’s attention to the subject, I doubt 
not but their labours would be deservedly crowned with success. 
The substance I used was that of a bullock’s bladder, as being 
the strongest and most flexible substance capable of being moulded 
to the proper form, that I could then procure to make my experi- 
ments ; but this substance we know is subject to a very rapid decay, 
especially when immersed in many fluids, 
