Problem of Irish church has forced postponement of Parliamentary discussion of metric bill until 13 May.

Sends copy of ST's Progress of Philosophy in the Past and in the Future.

Received JH's note. Will vote as JH advised. Bill is scheduled [to be read] on 13 May.

JH's account of his own health is much better than he hoped for. Has he seen AD's contribution to English?

[Printed notice] Invitation to meetings of 'Royal Geographical Society.'

Observations on various forms of [hemianopsia], which afflicts HA, his father [G. B. Airy], and JH. Detailed description of recent attack. Seven sketches with captions.

Thanks for JH's notes on metric system. Will study these before Parliamentary debate on 13 May. Calculates that 63 percent of exports go to British possessions, while only 18 percent go to Continent. Sees this as argument against introducing metric system.

Encloses papers from J. B. Smith, supporter of weights and measures bill. [JH's daughters] Maria and Amelia visited House [of Commons] yesterday, but ladies's gallery was full and they could not observe proceedings. Trial of American president [Andrew Johnson] is political farce.

Why did French chose arc from Dunkirk to Barcelona as basis for metric measurements? Explain meridian lines. Why are linear metric measurements founded on arc, rather than on straight line? Criticizes William Ewart for introducing metric bill.

Returns petition to JH. Read JH's paper. Venomous propositions [in House of Commons].

JH's approval encourages HA to publish account [of hemianopsia]. JH may keep HA's drawings. Notes on attack suffered by JH.

Informal request for JH to write biography of W. R. Dawes for R.A.S. Recent marriages in CP's family.

Sees what a majority William Ewart's bill had yesterday. Comments on the events leading to this. So glad of the marriage of Amelia Herschel.

More on musical scales [see GA's 1868-4-3]; GA here proposes the use of hyperbolic logarithms to help establish the scales.

Asks JH's approval for naming George Williams to take charge of Sinai survey fund following death of Pierce Butler. Will ask Secretary of State for War [J. S. Pakington] to place H. S. Palmer in charge and assign draftsmen and photographers to assist. Suggests survey goals. F. W. Holland agreed to join survey party. Estimated cost of survey is £1220.

Is sending William Pole's protest against the system of equal temperament in music [abstract of protest given].

Stating that the Board of Visitors could not afford to lose the services of JH.

Just received JH's paper. Will need two weeks to review it.

Thanks JH for his note. Asks that JH's paper on scales [1868 'On Musical Scales'] be made available to him.

Encloses biographical notes on W. R. Dawes.