Small glass pipe used as a gauge
                                Date
                            
                            
                                10 February 1664
                            
                            
                        
                            
                            
                            
                                Creator
                            
                            
                                Unknown, Artist
                            
                            
                        
                            
                            
                            
                                After
                            
                            
                                Robert Hooke (1635 - 1703, British) , Natural philosopher
                            
                            
                        
                            
                            
                            
                                Object type
                            
                            
                            
                        
                            
                            
                            
                                Archive reference number
                            
                            
                            
                        
                            
                            
                            
                                Manuscript page number
                            
                            
                                p139
                            
                            
                        
                            
                            
                            
                                Material
                            
                            
                            
                        
                            
                            
                            
                                Dimensions
                            
                            
                                height (page): 365mm
width (page): 233mm
                            
                        
                            
                            
                            width (page): 233mm
                                Subject
                            
                            
                            
                        
                            
                            
                            
                                Content object
                            
                            
                            
                        
                            
                            
                            
                                Description
                            
                            
                                Design of a glass gauge to measure the relative weight of air and water. The result of the experiment was reported to the meeting of the Royal Society on 10 February 1664.
This is a simplified copy of RBO/3/012. The original drawing by Hooke is at Cl.P/20/25/001.
                            
                            
                        
                            
                            
                            This is a simplified copy of RBO/3/012. The original drawing by Hooke is at Cl.P/20/25/001.
                                Transcription
                            
                            
                                ‘The gage was made of a small pipe of glass, of the shape represented in the figure A, B, C. The side AB was an even cylindrical pipe, full of air, closed at A: and the ball C was full of water, and the orifice D was left open, to let the air in or out, according to the exigency of the experiment; namely as the ambient air in the receiver was rarefied, the air contained in the cylinder AB rarefied itself likewise, and broke out into the receiver through the water in C; so that the air in AB was always of the rarity with the ambient air in the receiver, it forced the water contained in C into the cylindrical pipe AB, and filled twenty-three parts of twenty-four of it, leaving only a small bubble of air at the top, that filled 1/24 part of the whole cylinder: whence we collect, that there was only 1/24 part of the air, that had a little before filled it, when it was weighed in the scales.’
Transcribed by the Making Visible project
                            
                        
                            
                            
                            Transcribed by the Making Visible project
                                Object history
                            
                            
                                3 February 1664, ‘Mr. Hooke’s account both of the weight of the air in a large receiver 119 English wine pints, and of the proportion of the weight of the air to weight of the water, was read; and the latter was ordered to be repeated. It was ordered, that whoever made report of an experiment but once made, should repeat it, for the sake of more accuracy and certainty’ (Birch 1:377). 
10 February 1664, ‘The experiment concerning the weight of air, and the proportion of the weight of air to that of water, was repeated; of which Mr. Hooke was directed to give an account in writing at the meeting’ (Birch 1:379).
                            
                        
                            
                            
                            10 February 1664, ‘The experiment concerning the weight of air, and the proportion of the weight of air to that of water, was repeated; of which Mr. Hooke was directed to give an account in writing at the meeting’ (Birch 1:379).
                                Related fellows
                            
                            
                                Robert Hooke (1635 - 1703, British) , Natural philosopher
                            
                            
                        
                            
                            
                            
                                Associated place