Obliged by JH's letter. Would he let him know what he thinks of raising the matter of repeating John Southern's experiments. His own eldest son has gone to Langley; he shows little aptitude for figures but a decided turn for Natural History.

Will find the reference to S. D. Poisson in his own paper on the Heat of Vapours. The subject is in a state of confusion. John Southern's experiments are detailed in John Robison's Mechanical Philosophy, which can be sent from the R.S.L. library if JH does not possess it already.

Much obliged for JH calling but regrets he was out. The question [on steam] they have been discussing seems to be answered by a paper by a Prof. Karl Holtzmann he has just come across; comments on this. If JH is coming to S. J. A. Compton's (2nd Marquis of Northampton) soiree will he come and dine at St. James' Place?

Was not aware when he wrote his paper that doubt existed regarding the invariability of [the absolute heat of steam?]. Comments on the variations in the theories of S. D. Poisson and Karl Holtzmann. The experiments JH suggests would be highly interesting. Would he like to see Holtzmann's paper?

Has no doubt that any improvements JH suggests should be published. [John?] Taylor has borrowed Holtzmann's pamphlet, which will be sent as soon as returned. Karl Holtzmann's formula for air appears quite out. Gabriel Lamé evades the question. If JH writes anything on his calorimeter hopes he will mention the various questions raised.

Further regarding the various theories on the latent heat of steam. Agrees with JH regarding the magnetic observations. Hudson's Bay Company has sent a large bill for J. H. Lefroy's expenses, which the R.S.L. declines to pay. Fears that Edward Sabine is out of humor about something.

Now sees JH's point regarding the theory of steam. Comments on various experiments. Glad to see JH approves of repeating John Southern's experiments. Unable to go to Cambridge; his banking business requires unceasing attention. Doing all he can about the observations. Council will take up the East India observations.

Is JH aware that the magnetic and meteorological observations now being made at Greenwich are to cease at the end of the year? As JH was zealous for these observations he may care to write to S. J. A. Compton (2nd Marquis of Northampton). It escaped his notice that S. D. Poisson and J. B. Biot referred to saturated steam. Return John Robison and Karl Holtzmann to Mansion House when he has read them. Has consulted Thomas Graham about repeating John Southern's experiments.

Agrees with JH that the Government Observatories at the Cape and St. Helena require mature consideration. Greenwich observations are a different matter and were suggested by the R.S.L. Committee of Physics. Has directed the minute to be sent to JH. Has been studying the wet bulb question.

The magnetic and meteorological observatories were never part of any other system. Is not certain whether the Visitors had anything to do with these observatories. Captain Herbert in an Indian journal has proposed a formula for the wet bulb thermometer. Has arranged for the notice to be sent to JH.

The President was requested to write to the East India Company about the observatories. Continuance of the magnetic observations at Greenwich was referred to the Committee of Physics. Cannot find where Nicolas Clement-Desormes's observations are published. Has been studying the wet bulb problem. Capt. Herbert has denounced the article on hygrometry in Brewster's Encyclopaedia.

Has been with Philip Melvill of the East India Co. discussing the printing of the observations. Would it be a good use of JH's photographic papers to take a reverse of William Parsons' (3rd Earl of Rosse) drawings of nebulae? Cannot obtain Nicolas Clement-Desormes's or John Sharpe's papers. Doubts if the mode of measuring latent heat hitherto used can be recommended for accuracy.

Thanks JH for the receipt of a report of JH's work.

Thought his letter had miscarried. Thanks for the gift of his recently published work [Cape Results]. Will be glad to supply any information from his own work on comets, which he hopes to send in the course of a few days. Is studying U. J. J. Leverrier's method of development by elimination.

Regarding his own method of calculating the perturbations of the comets. Expense of computation is high for an individual and a mention by JH would bring support for his scheme. Would like to explain his method at an ordinary meeting in January. Every branch of science is facilitated by tables and those he suggests seem most desirable.

Is obliged by his note and will accordingly write to Richard Sheepshanks. Spot on the sun was very visible to the naked eye recently. Looks forward to seeing JH.

Even though he was Vice-Chancellor [of London University], he had no opportunity of becoming acquainted with the internal regulations of the colleges connected with the University. Regarding the education of young children. Sends some music for Lady Herschel. Would like them to pay him a visit.

Lady Lubbock has received a letter from a friend of JH's and it seems desirable that JH should know the contents. Can only communicate it verbally. Sends their congratulations on the forthcoming marriage of Miss Caroline Herschel.

Astronomer Royal and his wife are visiting the Lubbocks on Saturday; will JH join them for Saturday and Sunday? Will collect him if he likes. Louisa Herschel was the belle of the Bromley Ball.

Thinks there is nothing JH's son should be afraid of if the Directors will appoint him. Sorry to hear JH has been suffering. Lady Lubbock has been to St. Leonards.